Merge pull request #17264 from craftcms/bugfix/17260-slideout-panel-tabs

Tabs in a slideout

Author: brandonkelly

CHANGELOG.md

@@ -16,7 +16,7 @@
 - Fixed a bug where setting up two-step verification for an impersonated user would result in the original user getting logged back in. ([#17245](https://github.com/craftcms/cms/pull/17245))
 - Fixed a bug where conditionally-hidden entry Title fields were still being validated as required. ([#17249](https://github.com/craftcms/cms/issues/17249))
 - Fixed an error that could occur when upgrading to Craft 5. ([#17262](https://github.com/craftcms/cms/pull/17262))
-- Fixed styling issues. ([#17237](https://github.com/craftcms/cms/issues/17237), [#17261](https://github.com/craftcms/cms/pull/17261))
+- Fixed styling issues. ([#17237](https://github.com/craftcms/cms/issues/17237), [#17261](https://github.com/craftcms/cms/pull/17261), [#17264](https://github.com/craftcms/cms/pull/17264))
 
 ## 5.7.5 - 2025-05-06
 

src/controllers/ElementsController.php

@@ -396,7 +396,10 @@ public function actionEdit(?ElementInterface $element, ?int $elementId = null):
                 $canCreateDrafts,
             ))
             ->toolbarHtml(
-                Html::tag('div', options: ['class' => 'flex-grow']) .
+                // if we're in a slideout, we don't want to add the .flex-grow to the header toolbar
+                // as it'll mess with the width available for the tabs
+                // see https://github.com/craftcms/cms/issues/17260
+                ($this->_isSlideout() ? '' : Html::tag('div', options: ['class' => 'flex-grow'])) .
                 Html::tag('div', options: ['class' => 'activity-container']),
             )
             ->additionalButtonsHtml(fn() => $this->_additionalButtons(