[BUGFIX] Prevent submission of empty value in page title inline edit

Currently, it's possible to submit an empty page title in the
inline edit feature. If an empty title was submitted, the entire
element is gone.

This has been fixed by adding the 'required' attribute to
the input field.

Resolves: #100177
Releases: main
Change-Id: Ibdfa02da537301cf1f0bb65795356b090beb73d1
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78131


Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Benni Mack <benni@typo3.org>

Build/Sources/TypeScript/backend/element/editable-page-title.ts

@@ -220,7 +220,7 @@ export class EditablePageTitle extends LitElement {
   private composeEditForm(): TemplateResult {
     return html`
       <form class="wrapper" @submit="${ this.updatePageTitle }">
-        <input autocomplete="off" name="newPageTitle" ?disabled="${this._isSubmitting}" value="${this.pageTitle}" @keydown="${(e: KeyboardEvent): void => { if (e.key === 'Escape') { this.endEditing(); } }}">
+        <input autocomplete="off" required name="newPageTitle" ?disabled="${this._isSubmitting}" value="${this.pageTitle}" @keydown="${(e: KeyboardEvent): void => { if (e.key === 'Escape') { this.endEditing(); } }}">
         <button data-action="save" type="submit" ?disabled="${this._isSubmitting}">
           <typo3-backend-icon identifier="actions-check" size="small"></typo3-backend-icon>
         </button>

typo3/sysext/backend/Resources/Public/JavaScript/element/editable-page-title.js

@@ -19,7 +19,7 @@ var __decorate=function(t,e,i,o){var a,r=arguments.length,n=r<3?e:null===o?o=Obj
         <typo3-backend-icon identifier="actions-open" size="small"></typo3-backend-icon>
       </button>`}composeEditForm(){return html`
       <form class="wrapper" @submit="${this.updatePageTitle}">
-        <input autocomplete="off" name="newPageTitle" ?disabled="${this._isSubmitting}" value="${this.pageTitle}" @keydown="${t=>{"Escape"===t.key&&this.endEditing()}}">
+        <input autocomplete="off" required name="newPageTitle" ?disabled="${this._isSubmitting}" value="${this.pageTitle}" @keydown="${t=>{"Escape"===t.key&&this.endEditing()}}">
         <button data-action="save" type="submit" ?disabled="${this._isSubmitting}">
           <typo3-backend-icon identifier="actions-check" size="small"></typo3-backend-icon>
         </button>