diff --git a/plinth/modules/mediawiki/__init__.py b/plinth/modules/mediawiki/__init__.py
index e0534c9c1..c1d1b3887 100644
--- a/plinth/modules/mediawiki/__init__.py
+++ b/plinth/modules/mediawiki/__init__.py
@@ -14,7 +14,7 @@ from plinth.modules.backups.components import BackupRestore
 from plinth.modules.firewall.components import Firewall
 from plinth.package import Packages
 
-from . import manifest, privileged, forms
+from . import forms, manifest, privileged
 
 _description = [
     _('MediaWiki is the wiki engine that powers Wikipedia and other WikiMedia '
@@ -97,6 +97,11 @@ class MediaWikiApp(app_module.App):
         privileged.update()
         self.enable()
 
+    def uninstall(self):
+        """De-configure and uninstall the app."""
+        super().uninstall()
+        privileged.uninstall()
+
 
 class Shortcut(frontpage.Shortcut):
     """Frontpage shortcut for only logged users when in private mode."""
diff --git a/plinth/modules/mediawiki/privileged.py b/plinth/modules/mediawiki/privileged.py
index f78eff76c..7b319e17c 100644
--- a/plinth/modules/mediawiki/privileged.py
+++ b/plinth/modules/mediawiki/privileged.py
@@ -2,6 +2,8 @@
 """Configure MediaWiki."""
 
 import os
+import pathlib
+import shutil
 import subprocess
 import tempfile
 from typing import Optional
@@ -218,5 +220,11 @@ def set_default_language(language: str):
     # languages.
     rebuild_messages_script = os.path.join(MAINTENANCE_SCRIPTS_DIR,
                                            'rebuildmessages.php')
-    subprocess.check_call([
-        _get_php_command(), rebuild_messages_script])
+    subprocess.check_call([_get_php_command(), rebuild_messages_script])
+
+
+@privileged
+def uninstall():
+    """Remove Mediawiki's database and local config file."""
+    shutil.rmtree('/var/lib/mediawiki-db', ignore_errors=True)
+    pathlib.Path(LOCAL_SETTINGS_CONF).unlink(missing_ok=True)
diff --git a/plinth/modules/mediawiki/tests/test_functional.py b/plinth/modules/mediawiki/tests/test_functional.py
index 19a6a5523..b82afdc2e 100644
--- a/plinth/modules/mediawiki/tests/test_functional.py
+++ b/plinth/modules/mediawiki/tests/test_functional.py
@@ -100,6 +100,12 @@ class TestMediawikiApp(functional.BaseAppTests):
         assert _image_exists(session_browser, 'Noise.png')
         _verify_create_account_link(session_browser)
 
+    def test_uninstall(self, session_browser):
+        """Setup the app configuration again after a re-install."""
+        super().test_uninstall(session_browser)
+        _set_domain(session_browser)
+        _set_admin_password(session_browser, 'whatever123')
+
 
 def _enable_public_registrations(browser):
     """Enable public registrations in MediaWiki."""
@@ -213,6 +219,10 @@ def _delete_image(browser, username, password, image):
     path = f'/mediawiki/index.php?title=File:{image}&action=delete'
     functional.visit(browser, path)
     delete_button = browser.find_by_id('mw-filedelete-submit')
+    if not delete_button:
+        # On bookworm and higher
+        delete_button = browser.find_by_id('wpConfirmB')
+
     functional.submit(browser, element=delete_button)