diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index a8a67238fd..429510b8cf 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -12261,24 +12261,6 @@ parameters:
 			count: 1
 			path: src/Plugins/Export/ExportMediawiki.php
 
-		-
-			message: '#^Binary operation "\.\=" between mixed and ''\</office…'' results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOds.php
-
-		-
-			message: '#^Binary operation "\.\=" between mixed and ''\<\?xml version\="1\.0"…'' results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOds.php
-
-		-
-			message: '#^Binary operation "\.\=" between mixed and non\-falsy\-string results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOds.php
-
 		-
 			message: '''
 				#^Call to deprecated method getInstance\(\) of class PhpMyAdmin\\DatabaseInterface\:
@@ -12348,30 +12330,6 @@ parameters:
 			count: 1
 			path: src/Plugins/Export/ExportOdt.php
 
-		-
-			message: '#^Binary operation "\.\=" between mixed and ''\</office\:text\>\<…'' results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOdt.php
-
-		-
-			message: '#^Binary operation "\.\=" between mixed and ''\<\?xml version\="1\.0"…'' results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOdt.php
-
-		-
-			message: '#^Binary operation "\.\=" between mixed and ''\<text\:h text…'' results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 1
-			path: src/Plugins/Export/ExportOdt.php
-
-		-
-			message: '#^Binary operation "\.\=" between mixed and non\-falsy\-string results in an error\.$#'
-			identifier: assignOp.invalid
-			count: 8
-			path: src/Plugins/Export/ExportOdt.php
-
 		-
 			message: '''
 				#^Call to deprecated method getInstance\(\) of class PhpMyAdmin\\DatabaseInterface\:
@@ -21849,12 +21807,6 @@ parameters:
 			count: 1
 			path: tests/unit/Plugins/Export/ExportOdtTest.php
 
-		-
-			message: '#^Parameter \#2 \$haystack of static method PHPUnit\\Framework\\Assert\:\:assertStringContainsString\(\) expects string, mixed given\.$#'
-			identifier: argument.type
-			count: 11
-			path: tests/unit/Plugins/Export/ExportOdtTest.php
-
 		-
 			message: '''
 				#^Call to deprecated method getInstance\(\) of class PhpMyAdmin\\Config\:
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 6e8cf17354..31700c919b 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -13199,11 +13199,6 @@
       <code><![CDATA[$config->selectedServer]]></code>
     </InvalidPropertyAssignmentValue>
   </file>
-  <file src="tests/unit/Plugins/Export/ExportOdsTest.php">
-    <TypeDoesNotContainType>
-      <code><![CDATA[assertSame]]></code>
-    </TypeDoesNotContainType>
-  </file>
   <file src="tests/unit/Plugins/Export/ExportOdtTest.php">
     <DeprecatedMethod>
       <code><![CDATA[Config::getInstance()]]></code>
@@ -13217,12 +13212,6 @@
     <MixedAssignment>
       <code><![CDATA[$result]]></code>
     </MixedAssignment>
-    <TypeDoesNotContainType>
-      <code><![CDATA[assertSame]]></code>
-      <code><![CDATA[assertSame]]></code>
-      <code><![CDATA[assertSame]]></code>
-      <code><![CDATA[assertSame]]></code>
-    </TypeDoesNotContainType>
   </file>
   <file src="tests/unit/Plugins/Export/ExportSqlTest.php">
     <DeprecatedMethod>
diff --git a/psalm.xml b/psalm.xml
index ed8bf5c3b1..df8e45f7a6 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -78,8 +78,6 @@
             maxsize: string,
             memory_limit: int,
             message: PhpMyAdmin\Message,
-            ods_buffer: string,
-            odt_buffer: string,
             offset: int,
             old_tz: string,
             onfly_compression: bool,
diff --git a/src/Plugins/Export/ExportOds.php b/src/Plugins/Export/ExportOds.php
index 05180c8eb1..0c34419ed8 100644
--- a/src/Plugins/Export/ExportOds.php
+++ b/src/Plugins/Export/ExportOds.php
@@ -32,9 +32,11 @@ use function strtotime;
  */
 class ExportOds extends ExportPlugin
 {
+    public string $buffer = '';
+
     protected function init(): void
     {
-        $GLOBALS['ods_buffer'] = '';
+        $this->buffer = '';
     }
 
     /** @psalm-return non-empty-lowercase-string */
@@ -86,7 +88,7 @@ class ExportOds extends ExportPlugin
      */
     public function exportHeader(): bool
     {
-        $GLOBALS['ods_buffer'] .= '<?xml version="1.0" encoding="utf-8"?' . '>'
+        $this->buffer .= '<?xml version="1.0" encoding="utf-8"?>'
             . '<office:document-content '
             . OpenDocument::NS . ' office:version="1.0">'
             . '<office:automatic-styles>'
@@ -140,12 +142,12 @@ class ExportOds extends ExportPlugin
      */
     public function exportFooter(): bool
     {
-        $GLOBALS['ods_buffer'] .= '</office:spreadsheet></office:body></office:document-content>';
+        $this->buffer .= '</office:spreadsheet></office:body></office:document-content>';
 
         return $this->export->outputHandler(
             OpenDocument::create(
                 'application/vnd.oasis.opendocument.spreadsheet',
-                $GLOBALS['ods_buffer'],
+                $this->buffer,
             ),
         );
     }
@@ -205,30 +207,30 @@ class ExportOds extends ExportPlugin
         $fieldsCnt = $result->numFields();
         $fieldsMeta = $dbi->getFieldsMeta($result);
 
-        $GLOBALS['ods_buffer'] .= '<table:table table:name="' . htmlspecialchars($tableAlias) . '">';
+        $this->buffer .= '<table:table table:name="' . htmlspecialchars($tableAlias) . '">';
 
         // If required, get fields name at the first line
         if (isset($GLOBALS['ods_columns'])) {
-            $GLOBALS['ods_buffer'] .= '<table:table-row>';
+            $this->buffer .= '<table:table-row>';
             foreach ($fieldsMeta as $field) {
                 $colAs = $field->name;
                 if (! empty($aliases[$db]['tables'][$table]['columns'][$colAs])) {
                     $colAs = $aliases[$db]['tables'][$table]['columns'][$colAs];
                 }
 
-                $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="string">'
+                $this->buffer .= '<table:table-cell office:value-type="string">'
                     . '<text:p>'
                     . htmlspecialchars($colAs)
                     . '</text:p>'
                     . '</table:table-cell>';
             }
 
-            $GLOBALS['ods_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
         // Format the data
         while ($row = $result->fetchRow()) {
-            $GLOBALS['ods_buffer'] .= '<table:table-row>';
+            $this->buffer .= '<table:table-row>';
             /** @infection-ignore-all */
             for ($j = 0; $j < $fieldsCnt; $j++) {
                 if ($fieldsMeta[$j]->isMappedTypeGeometry) {
@@ -237,18 +239,18 @@ class ExportOds extends ExportPlugin
                 }
 
                 if (! isset($row[$j])) {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($GLOBALS['ods_null'])
                         . '</text:p>'
                         . '</table:table-cell>';
                 } elseif ($fieldsMeta[$j]->isBinary && $fieldsMeta[$j]->isBlob) {
                     // ignore BLOB
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p></text:p>'
                         . '</table:table-cell>';
                 } elseif ($fieldsMeta[$j]->isType(FieldMetadata::TYPE_DATE)) {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="date"'
+                    $this->buffer .= '<table:table-cell office:value-type="date"'
                         . ' office:date-value="'
                         . date('Y-m-d', strtotime($row[$j]))
                         . '" table:style-name="DateCell">'
@@ -257,7 +259,7 @@ class ExportOds extends ExportPlugin
                         . '</text:p>'
                         . '</table:table-cell>';
                 } elseif ($fieldsMeta[$j]->isType(FieldMetadata::TYPE_TIME)) {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="time"'
+                    $this->buffer .= '<table:table-cell office:value-type="time"'
                         . ' office:time-value="'
                         . date('\P\TH\Hi\Ms\S', strtotime($row[$j]))
                         . '" table:style-name="TimeCell">'
@@ -266,7 +268,7 @@ class ExportOds extends ExportPlugin
                         . '</text:p>'
                         . '</table:table-cell>';
                 } elseif ($fieldsMeta[$j]->isType(FieldMetadata::TYPE_DATETIME)) {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="date"'
+                    $this->buffer .= '<table:table-cell office:value-type="date"'
                         . ' office:date-value="'
                         . date('Y-m-d\TH:i:s', strtotime($row[$j]))
                         . '" table:style-name="DateTimeCell">'
@@ -277,14 +279,14 @@ class ExportOds extends ExportPlugin
                 } elseif (
                     $fieldsMeta[$j]->isNumeric
                 ) {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="float"'
+                    $this->buffer .= '<table:table-cell office:value-type="float"'
                         . ' office:value="' . $row[$j] . '" >'
                         . '<text:p>'
                         . htmlspecialchars($row[$j])
                         . '</text:p>'
                         . '</table:table-cell>';
                 } else {
-                    $GLOBALS['ods_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($row[$j])
                         . '</text:p>'
@@ -292,10 +294,10 @@ class ExportOds extends ExportPlugin
                 }
             }
 
-            $GLOBALS['ods_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
-        $GLOBALS['ods_buffer'] .= '</table:table>';
+        $this->buffer .= '</table:table>';
 
         return true;
     }
diff --git a/src/Plugins/Export/ExportOdt.php b/src/Plugins/Export/ExportOdt.php
index 635f2cd552..69af06e373 100644
--- a/src/Plugins/Export/ExportOdt.php
+++ b/src/Plugins/Export/ExportOdt.php
@@ -35,15 +35,14 @@ use function str_replace;
  */
 class ExportOdt extends ExportPlugin
 {
+    public string $buffer = '';
     private bool $doRelation = false;
-
     private bool $doMime = false;
-
     private bool $doComments = false;
 
     protected function init(): void
     {
-        $GLOBALS['odt_buffer'] = '';
+        $this->buffer = '';
     }
 
     /** @psalm-return non-empty-lowercase-string */
@@ -150,7 +149,7 @@ class ExportOdt extends ExportPlugin
      */
     public function exportHeader(): bool
     {
-        $GLOBALS['odt_buffer'] .= '<?xml version="1.0" encoding="utf-8"?' . '>'
+        $this->buffer .= '<?xml version="1.0" encoding="utf-8"?>'
             . '<office:document-content '
             . OpenDocument::NS . ' office:version="1.0">'
             . '<office:body>'
@@ -164,11 +163,11 @@ class ExportOdt extends ExportPlugin
      */
     public function exportFooter(): bool
     {
-        $GLOBALS['odt_buffer'] .= '</office:text></office:body></office:document-content>';
+        $this->buffer .= '</office:text></office:body></office:document-content>';
 
         return $this->export->outputHandler(OpenDocument::create(
             'application/vnd.oasis.opendocument.text',
-            $GLOBALS['odt_buffer'],
+            $this->buffer,
         ));
     }
 
@@ -184,7 +183,7 @@ class ExportOdt extends ExportPlugin
             $dbAlias = $db;
         }
 
-        $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="1" text:style-name="Heading_1"'
+        $this->buffer .= '<text:h text:outline-level="1" text:style-name="Heading_1"'
             . ' text:is-list-header="true">'
             . __('Database') . ' ' . htmlspecialchars($dbAlias)
             . '</text:h>';
@@ -236,12 +235,12 @@ class ExportOdt extends ExportPlugin
         $fieldsCnt = $result->numFields();
         $fieldsMeta = $dbi->getFieldsMeta($result);
 
-        $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
+        $this->buffer .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
             . ' text:is-list-header="true">';
         $tableAlias != ''
-            ? $GLOBALS['odt_buffer'] .= __('Dumping data for table') . ' ' . htmlspecialchars($tableAlias)
-            : $GLOBALS['odt_buffer'] .= __('Dumping data for query result');
-        $GLOBALS['odt_buffer'] .= '</text:h>'
+            ? $this->buffer .= __('Dumping data for table') . ' ' . htmlspecialchars($tableAlias)
+            : $this->buffer .= __('Dumping data for query result');
+        $this->buffer .= '</text:h>'
             . '<table:table'
             . ' table:name="' . htmlspecialchars($tableAlias) . '_structure">'
             . '<table:table-column'
@@ -249,26 +248,26 @@ class ExportOdt extends ExportPlugin
 
         // If required, get fields name at the first line
         if (isset($GLOBALS['odt_columns'])) {
-            $GLOBALS['odt_buffer'] .= '<table:table-row>';
+            $this->buffer .= '<table:table-row>';
             foreach ($fieldsMeta as $field) {
                 $colAs = $field->name;
                 if (! empty($aliases[$db]['tables'][$table]['columns'][$colAs])) {
                     $colAs = $aliases[$db]['tables'][$table]['columns'][$colAs];
                 }
 
-                $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                $this->buffer .= '<table:table-cell office:value-type="string">'
                     . '<text:p>'
                     . htmlspecialchars($colAs)
                     . '</text:p>'
                     . '</table:table-cell>';
             }
 
-            $GLOBALS['odt_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
         // Format the data
         while ($row = $result->fetchRow()) {
-            $GLOBALS['odt_buffer'] .= '<table:table-row>';
+            $this->buffer .= '<table:table-row>';
             /** @infection-ignore-all */
             for ($j = 0; $j < $fieldsCnt; $j++) {
                 if ($fieldsMeta[$j]->isMappedTypeGeometry) {
@@ -277,27 +276,27 @@ class ExportOdt extends ExportPlugin
                 }
 
                 if (! isset($row[$j])) {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($GLOBALS['odt_null'])
                         . '</text:p>'
                         . '</table:table-cell>';
                 } elseif ($fieldsMeta[$j]->isBinary && $fieldsMeta[$j]->isBlob) {
                     // ignore BLOB
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p></text:p>'
                         . '</table:table-cell>';
                 } elseif (
                     $fieldsMeta[$j]->isNumeric
                 ) {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="float"'
+                    $this->buffer .= '<table:table-cell office:value-type="float"'
                         . ' office:value="' . $row[$j] . '" >'
                         . '<text:p>'
                         . htmlspecialchars($row[$j])
                         . '</text:p>'
                         . '</table:table-cell>';
                 } else {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($row[$j])
                         . '</text:p>'
@@ -305,10 +304,10 @@ class ExportOdt extends ExportPlugin
                 }
             }
 
-            $GLOBALS['odt_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
-        $GLOBALS['odt_buffer'] .= '</table:table>';
+        $this->buffer .= '</table:table>';
 
         return true;
     }
@@ -351,13 +350,13 @@ class ExportOdt extends ExportPlugin
         /**
          * Displays the table structure
          */
-        $GLOBALS['odt_buffer'] .= '<table:table table:name="'
+        $this->buffer .= '<table:table table:name="'
             . htmlspecialchars($viewAlias) . '_data">';
         $columnsCnt = 4;
-        $GLOBALS['odt_buffer'] .= '<table:table-column'
+        $this->buffer .= '<table:table-column'
             . ' table:number-columns-repeated="' . $columnsCnt . '"/>';
         /* Header */
-        $GLOBALS['odt_buffer'] .= '<table:table-row>'
+        $this->buffer .= '<table:table-row>'
             . '<table:table-cell office:value-type="string">'
             . '<text:p>' . __('Column') . '</text:p>'
             . '</table:table-cell>'
@@ -379,11 +378,11 @@ class ExportOdt extends ExportPlugin
                 $colAs = $aliases[$db]['tables'][$view]['columns'][$colAs];
             }
 
-            $GLOBALS['odt_buffer'] .= $this->formatOneColumnDefinition($column, $colAs);
-            $GLOBALS['odt_buffer'] .= '</table:table-row>';
+            $this->buffer .= $this->formatOneColumnDefinition($column, $colAs);
+            $this->buffer .= '</table:table-row>';
         }
 
-        $GLOBALS['odt_buffer'] .= '</table:table>';
+        $this->buffer .= '</table:table>';
 
         return '';
     }
@@ -416,7 +415,7 @@ class ExportOdt extends ExportPlugin
         /**
          * Displays the table structure
          */
-        $GLOBALS['odt_buffer'] .= '<table:table table:name="'
+        $this->buffer .= '<table:table table:name="'
             . htmlspecialchars($tableAlias) . '_structure">';
         $columnsCnt = 4;
         if ($this->doRelation && $foreigners !== []) {
@@ -431,10 +430,10 @@ class ExportOdt extends ExportPlugin
             $columnsCnt++;
         }
 
-        $GLOBALS['odt_buffer'] .= '<table:table-column'
+        $this->buffer .= '<table:table-column'
             . ' table:number-columns-repeated="' . $columnsCnt . '"/>';
         /* Header */
-        $GLOBALS['odt_buffer'] .= '<table:table-row>'
+        $this->buffer .= '<table:table-row>'
             . '<table:table-cell office:value-type="string">'
             . '<text:p>' . __('Column') . '</text:p>'
             . '</table:table-cell>'
@@ -448,26 +447,26 @@ class ExportOdt extends ExportPlugin
             . '<text:p>' . __('Default') . '</text:p>'
             . '</table:table-cell>';
         if ($this->doRelation && $foreigners !== []) {
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>' . __('Links to') . '</text:p>'
                 . '</table:table-cell>';
         }
 
         if ($this->doComments) {
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>' . __('Comments') . '</text:p>'
                 . '</table:table-cell>';
             $comments = $this->relation->getComments($db, $table);
         }
 
         if ($this->doMime && $relationParameters->browserTransformationFeature !== null) {
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>' . __('Media type') . '</text:p>'
                 . '</table:table-cell>';
             $mimeMap = $this->transformations->getMime($db, $table, true);
         }
 
-        $GLOBALS['odt_buffer'] .= '</table:table-row>';
+        $this->buffer .= '</table:table-row>';
 
         $columns = $dbi->getColumns($db, $table);
         foreach ($columns as $column) {
@@ -476,7 +475,7 @@ class ExportOdt extends ExportPlugin
                 $colAs = $aliases[$db]['tables'][$table]['columns'][$colAs];
             }
 
-            $GLOBALS['odt_buffer'] .= $this->formatOneColumnDefinition($column, $colAs);
+            $this->buffer .= $this->formatOneColumnDefinition($column, $colAs);
             if ($this->doRelation && $foreigners !== []) {
                 $foreigner = $this->relation->searchColumnInForeigners($foreigners, $fieldName);
                 if ($foreigner) {
@@ -491,7 +490,7 @@ class ExportOdt extends ExportPlugin
                     }
 
                     $relation = htmlspecialchars($rtable . ' (' . $rfield . ')');
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($relation)
                         . '</text:p>'
@@ -501,13 +500,13 @@ class ExportOdt extends ExportPlugin
 
             if ($this->doComments) {
                 if (isset($comments[$fieldName])) {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars($comments[$fieldName])
                         . '</text:p>'
                         . '</table:table-cell>';
                 } else {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p></text:p>'
                         . '</table:table-cell>';
                 }
@@ -515,7 +514,7 @@ class ExportOdt extends ExportPlugin
 
             if ($this->doMime && $relationParameters->browserTransformationFeature !== null) {
                 if (isset($mimeMap[$fieldName])) {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p>'
                         . htmlspecialchars(
                             str_replace('_', '/', $mimeMap[$fieldName]['mimetype']),
@@ -523,16 +522,16 @@ class ExportOdt extends ExportPlugin
                         . '</text:p>'
                         . '</table:table-cell>';
                 } else {
-                    $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+                    $this->buffer .= '<table:table-cell office:value-type="string">'
                         . '<text:p></text:p>'
                         . '</table:table-cell>';
                 }
             }
 
-            $GLOBALS['odt_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
-        $GLOBALS['odt_buffer'] .= '</table:table>';
+        $this->buffer .= '</table:table>';
 
         return true;
     }
@@ -545,7 +544,7 @@ class ExportOdt extends ExportPlugin
      */
     protected function getTriggers(string $table, array $triggers): string
     {
-        $GLOBALS['odt_buffer'] .= '<table:table'
+        $this->buffer .= '<table:table'
             . ' table:name="' . htmlspecialchars($table) . '_triggers">'
             . '<table:table-column'
             . ' table:number-columns-repeated="4"/>'
@@ -565,33 +564,33 @@ class ExportOdt extends ExportPlugin
             . '</table:table-row>';
 
         foreach ($triggers as $trigger) {
-            $GLOBALS['odt_buffer'] .= '<table:table-row>';
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-row>';
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>'
                 . htmlspecialchars($trigger->name->getName())
                 . '</text:p>'
                 . '</table:table-cell>';
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>'
                 . htmlspecialchars($trigger->timing->value)
                 . '</text:p>'
                 . '</table:table-cell>';
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>'
                 . htmlspecialchars($trigger->event->value)
                 . '</text:p>'
                 . '</table:table-cell>';
-            $GLOBALS['odt_buffer'] .= '<table:table-cell office:value-type="string">'
+            $this->buffer .= '<table:table-cell office:value-type="string">'
                 . '<text:p>'
                 . htmlspecialchars($trigger->statement)
                 . '</text:p>'
                 . '</table:table-cell>';
-            $GLOBALS['odt_buffer'] .= '</table:table-row>';
+            $this->buffer .= '</table:table-row>';
         }
 
-        $GLOBALS['odt_buffer'] .= '</table:table>';
+        $this->buffer .= '</table:table>';
 
-        return $GLOBALS['odt_buffer'];
+        return $this->buffer;
     }
 
     /**
@@ -609,7 +608,7 @@ class ExportOdt extends ExportPlugin
         $this->initAlias($aliases, $dbAlias, $tableAlias);
         switch ($exportMode) {
             case 'create_table':
-                $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
+                $this->buffer .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
                 . ' text:is-list-header="true">'
                 . __('Table structure for table') . ' ' .
                 htmlspecialchars($tableAlias)
@@ -619,7 +618,7 @@ class ExportOdt extends ExportPlugin
             case 'triggers':
                 $triggers = Triggers::getDetails(DatabaseInterface::getInstance(), $db, $table);
                 if ($triggers !== []) {
-                    $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
+                    $this->buffer .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
                     . ' text:is-list-header="true">'
                     . __('Triggers') . ' '
                     . htmlspecialchars($tableAlias)
@@ -629,7 +628,7 @@ class ExportOdt extends ExportPlugin
 
                 break;
             case 'create_view':
-                $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
+                $this->buffer .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
                 . ' text:is-list-header="true">'
                 . __('Structure for view') . ' '
                 . htmlspecialchars($tableAlias)
@@ -637,7 +636,7 @@ class ExportOdt extends ExportPlugin
                 $this->getTableDef($db, $table, $aliases);
                 break;
             case 'stand_in':
-                $GLOBALS['odt_buffer'] .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
+                $this->buffer .= '<text:h text:outline-level="2" text:style-name="Heading_2"'
                 . ' text:is-list-header="true">'
                 . __('Stand-in structure for view') . ' '
                 . htmlspecialchars($tableAlias)
diff --git a/tests/unit/Plugins/Export/ExportOdsTest.php b/tests/unit/Plugins/Export/ExportOdsTest.php
index a2dd492aa2..8c7ac551a7 100644
--- a/tests/unit/Plugins/Export/ExportOdsTest.php
+++ b/tests/unit/Plugins/Export/ExportOdsTest.php
@@ -171,23 +171,24 @@ class ExportOdsTest extends AbstractTestCase
 
     public function testExportHeader(): void
     {
-        self::assertArrayHasKey('ods_buffer', $GLOBALS);
-
-        self::assertTrue(
-            $this->object->exportHeader(),
+        $this->object->buffer = '';
+        self::assertTrue($this->object->exportHeader());
+        self::assertStringStartsWith(
+            '<?xml version="1.0" encoding="utf-8"?><office:document-content',
+            $this->object->buffer,
         );
     }
 
     public function testExportFooter(): void
     {
-        $GLOBALS['ods_buffer'] = 'header';
+        $this->object->buffer = 'header';
         self::assertTrue($this->object->exportFooter());
         $output = $this->getActualOutputForAssertion();
         self::assertMatchesRegularExpression('/^504b.*636f6e74656e742e786d6c/', bin2hex($output));
-        self::assertStringContainsString('header', $GLOBALS['ods_buffer']);
-        self::assertStringContainsString('</office:spreadsheet>', $GLOBALS['ods_buffer']);
-        self::assertStringContainsString('</office:body>', $GLOBALS['ods_buffer']);
-        self::assertStringContainsString('</office:document-content>', $GLOBALS['ods_buffer']);
+        self::assertStringContainsString('header', $this->object->buffer);
+        self::assertStringContainsString('</office:spreadsheet>', $this->object->buffer);
+        self::assertStringContainsString('</office:body>', $this->object->buffer);
+        self::assertStringContainsString('</office:document-content>', $this->object->buffer);
     }
 
     public function testExportDBHeader(): void
@@ -284,7 +285,7 @@ class ExportOdsTest extends AbstractTestCase
             'office:value="a&b" ><text:p>a&amp;b</text:p></table:table-cell>' .
             '<table:table-cell office:value-type="string"><text:p>&lt;</text:p>' .
             '</table:table-cell></table:table-row></table:table>',
-            $GLOBALS['ods_buffer'],
+            $this->object->buffer,
         );
     }
 
@@ -347,7 +348,7 @@ class ExportOdsTest extends AbstractTestCase
             '-cell><table:table-cell office:value-type="string"><text:p>' .
             'fnam/&lt;e2</text:p></table:table-cell></table:table-row>' .
             '</table:table>',
-            $GLOBALS['ods_buffer'],
+            $this->object->buffer,
         );
 
         // with no row count
@@ -381,7 +382,7 @@ class ExportOdsTest extends AbstractTestCase
         $GLOBALS['mediawiki_caption'] = true;
         $GLOBALS['mediawiki_headers'] = true;
         $GLOBALS['ods_null'] = '&';
-        $GLOBALS['ods_buffer'] = '';
+        $this->object->buffer = '';
 
         self::assertTrue(
             $this->object->exportData(
@@ -393,7 +394,7 @@ class ExportOdsTest extends AbstractTestCase
 
         self::assertSame(
             '<table:table table:name="table"><table:table-row></table:table-row></table:table>',
-            $GLOBALS['ods_buffer'],
+            $this->object->buffer,
         );
     }
 }
diff --git a/tests/unit/Plugins/Export/ExportOdtTest.php b/tests/unit/Plugins/Export/ExportOdtTest.php
index ed9fe592a9..b9a1fe0229 100644
--- a/tests/unit/Plugins/Export/ExportOdtTest.php
+++ b/tests/unit/Plugins/Export/ExportOdtTest.php
@@ -312,34 +312,34 @@ class ExportOdtTest extends AbstractTestCase
             $this->object->exportHeader(),
         );
 
-        self::assertStringContainsString('<office:document-content', $GLOBALS['odt_buffer']);
-        self::assertStringContainsString('office:version', $GLOBALS['odt_buffer']);
+        self::assertStringContainsString('<office:document-content', $this->object->buffer);
+        self::assertStringContainsString('office:version', $this->object->buffer);
     }
 
     public function testExportFooter(): void
     {
-        $GLOBALS['odt_buffer'] = 'header';
+        $this->object->buffer = 'header';
         self::assertTrue($this->object->exportFooter());
         $output = $this->getActualOutputForAssertion();
         self::assertMatchesRegularExpression('/^504b.*636f6e74656e742e786d6c/', bin2hex($output));
-        self::assertStringContainsString('header', $GLOBALS['odt_buffer']);
+        self::assertStringContainsString('header', $this->object->buffer);
         self::assertStringContainsString(
             '</office:text></office:body></office:document-content>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
     }
 
     public function testExportDBHeader(): void
     {
-        $GLOBALS['odt_buffer'] = 'header';
+        $this->object->buffer = 'header';
 
         self::assertTrue(
             $this->object->exportDBHeader('d&b'),
         );
 
-        self::assertStringContainsString('header', $GLOBALS['odt_buffer']);
+        self::assertStringContainsString('header', $this->object->buffer);
 
-        self::assertStringContainsString('Database d&amp;b</text:h>', $GLOBALS['odt_buffer']);
+        self::assertStringContainsString('Database d&amp;b</text:h>', $this->object->buffer);
     }
 
     public function testExportDBFooter(): void
@@ -416,7 +416,7 @@ class ExportOdtTest extends AbstractTestCase
             '</table:table-cell><table:table-cell office:value-type="string">' .
             '<text:p>a&amp;b</text:p></table:table-cell></table:table-row>' .
             '</table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
     }
 
@@ -479,7 +479,7 @@ class ExportOdtTest extends AbstractTestCase
             'value-type="string"><text:p>fna\&quot;me</text:p></table:table-cell>' .
             '<table:table-cell office:value-type="string"><text:p>fnam/&lt;e2' .
             '</text:p></table:table-cell></table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         // with no row count
@@ -513,7 +513,7 @@ class ExportOdtTest extends AbstractTestCase
         $GLOBALS['mediawiki_caption'] = true;
         $GLOBALS['mediawiki_headers'] = true;
         $GLOBALS['odt_null'] = '&';
-        $GLOBALS['odt_buffer'] = '';
+        $this->object->buffer = '';
 
         self::assertTrue(
             $this->object->exportData(
@@ -529,7 +529,7 @@ class ExportOdtTest extends AbstractTestCase
             '<table:table table:name="table_structure"><table:table-column ' .
             'table:number-columns-repeated="0"/><table:table-row>' .
             '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
     }
 
@@ -565,7 +565,7 @@ class ExportOdtTest extends AbstractTestCase
             . '<table:table-cell office:value-type="string"><text:p>No</text:p></table:table-cell>'
             . '<table:table-cell office:value-type="string"><text:p>NULL</text:p></table:table-cell>'
             . '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
     }
 
@@ -636,17 +636,17 @@ class ExportOdtTest extends AbstractTestCase
 
         self::assertStringContainsString(
             '<table:table table:name="_structure"><table:table-column table:number-columns-repeated="6"/>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         self::assertStringContainsString(
             '<table:table-cell office:value-type="string"><text:p>Comments</text:p></table:table-cell>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         self::assertStringContainsString(
             '<table:table-cell office:value-type="string"><text:p>Media type</text:p></table:table-cell>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         self::assertStringContainsString(
@@ -654,7 +654,7 @@ class ExportOdtTest extends AbstractTestCase
             '<text:p></text:p></table:table-cell><table:table-cell office:value-' .
             'type="string"><text:p>Test&lt;</text:p></table:table-cell>' .
             '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         // case 2
@@ -692,7 +692,7 @@ class ExportOdtTest extends AbstractTestCase
 
         DatabaseInterface::$instance = $dbi;
         $this->object->relation = new Relation($dbi);
-        $GLOBALS['odt_buffer'] = '';
+        $this->object->buffer = '';
         $relationParameters = RelationParameters::fromArray([
             'relwork' => true,
             'commwork' => true,
@@ -705,7 +705,7 @@ class ExportOdtTest extends AbstractTestCase
 
         self::assertTrue($this->object->getTableDef('database', ''));
 
-        self::assertStringContainsString('<text:p>ftable (ffield)</text:p>', $GLOBALS['odt_buffer']);
+        self::assertStringContainsString('<text:p>ftable (ffield)</text:p>', $this->object->buffer);
     }
 
     public function testGetTriggers(): void
@@ -724,7 +724,7 @@ class ExportOdtTest extends AbstractTestCase
         $method = new ReflectionMethod(ExportOdt::class, 'getTriggers');
         $result = $method->invoke($this->object, 'ta<ble', $triggers);
 
-        self::assertSame($result, $GLOBALS['odt_buffer']);
+        self::assertSame($result, $this->object->buffer);
 
         self::assertStringContainsString('<table:table table:name="ta&lt;ble_triggers">', $result);
 
@@ -768,11 +768,11 @@ class ExportOdtTest extends AbstractTestCase
             . '<table:table-cell office:value-type="string"><text:p>No</text:p></table:table-cell>'
             . '<table:table-cell office:value-type="string"><text:p>NULL</text:p></table:table-cell>'
             . '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         // case 2
-        $GLOBALS['odt_buffer'] = '';
+        $this->object->buffer = '';
 
         self::assertTrue($this->object->exportStructure('test_db', 'test_table', 'triggers'));
 
@@ -790,11 +790,11 @@ class ExportOdtTest extends AbstractTestCase
             . '<table:table-cell office:value-type="string"><text:p>INSERT</text:p></table:table-cell>'
             . '<table:table-cell office:value-type="string"><text:p>BEGIN END</text:p></table:table-cell>'
             . '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         // case 3
-        $GLOBALS['odt_buffer'] = '';
+        $this->object->buffer = '';
 
         $this->dummyDbi->addSelectDb('test_db');
         self::assertTrue($this->object->exportStructure('test_db', 'test_table', 'create_view'));
@@ -824,12 +824,12 @@ class ExportOdtTest extends AbstractTestCase
             . '<table:table-cell office:value-type="string"><text:p>No</text:p></table:table-cell>'
             . '<table:table-cell office:value-type="string"><text:p>NULL</text:p></table:table-cell>'
             . '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
 
         // case 4
         $this->dummyDbi->addSelectDb('test_db');
-        $GLOBALS['odt_buffer'] = '';
+        $this->object->buffer = '';
         self::assertTrue($this->object->exportStructure('test_db', 'test_table', 'stand_in'));
         $this->dummyDbi->assertAllSelectsConsumed();
 
@@ -857,7 +857,7 @@ class ExportOdtTest extends AbstractTestCase
             . '<table:table-cell office:value-type="string"><text:p>No</text:p></table:table-cell>'
             . '<table:table-cell office:value-type="string"><text:p>NULL</text:p></table:table-cell>'
             . '</table:table-row></table:table>',
-            $GLOBALS['odt_buffer'],
+            $this->object->buffer,
         );
     }