TYPO3 12.4.35

13 August 2025

TYPO3 version 12.4.35 is now available.

Upgrading to TYPO3 12.4.35

What's New in TYPO3 12.4.35

• [BUGFIX] Do not set default action in filename conflict modal (thanks to Andreas Wolf)
  
• [DOCS] Improve FAQ about duplicate form submission (thanks to josuavogel)
  
• [BUGFIX] Handle oversights in thumbnail web component (thanks to Andreas Kienast)
  
• [DOCS] Add line break after anchor (thanks to Jan Helke)
  
• [DOCS] Add headline anchor to EXT:sys_note header (thanks to magicHatOfTYPO3)
  
• [DOCS] Add headline anchor to EXT:lowlevel header (thanks to magicHatOfTYPO3)
  
• [BUGFIX] Add svg/avif/webp to IIS default web.config (thanks to Michael Blunck)
  
• [TASK] Upgrade TypeScript to v5.9 (thanks to Andreas Kienast)
  
• [BUGFIX] Check for existing category before processing it (thanks to David Retzer)
  
• [TASK] Update phpstan/phpstan to 2.1.22 (thanks to Andreas Kienast)
  
• [BUGFIX] Fix default value of TYPO3_CONF_VARS/BE/lockRootPath (thanks to Albrecht Köhnlein)
  
• [BUGFIX] RedisSessionBackend must allow to select db 0 (thanks to Markus Klein)
  
• [TASK] Improve Sudo Mode prompt with explanation (thanks to Oliver Bartsch)
  
• [DOCS] Fix typo in changelog (thanks to Simon Praetorius)
  
• [TASK] Update masterminds/html5 dependency (thanks to Oliver Hader)
  
• [BUGFIX] Offload decorative thumbnail generation in file list (thanks to Andreas Kienast)
  
• [BUGFIX] Set correct data-mode for file selection (thanks to Oliver Bartsch)
  
• [BUGFIX] Enable inline SVG support in typo3/html-sanitizer (thanks to Oliver Hader)
  
• [BUGFIX] Check correct file location in DeferredBackendImageProcessor (thanks to Markus Klein)
  
• [BUGFIX] Fix step-up response redirect routing in modals (thanks to Benjamin Franzke)
  
• [DOCS] Fix rendering for changelog (thanks to Sybille)
  
• [TASK] Update phpstan/phpstan to 2.1.19 (thanks to Garvin Hicking)
  
• [BUGFIX] Disable indexing of seo_sitemap (thanks to Stephan Großberndt)
  
• [BUGFIX] Ensure request body is writable in ServerRequestInstruction (thanks to Oliver Bartsch)
  
• [TASK] Update phpstan/phpstan to 2.1.18 (thanks to Garvin Hicking)
  
• [DOCS] Properly use siteLanguage(“locale”) expression as object (thanks to josuavogel)
  
• [TASK] Allow execution with PHP8.5 in Build/Scripts/runTests.sh (thanks to Stefan Bürk)
  

• [TASK] Re-add legacy MimeTypeNotAllowedForFileExtension XLF label (thanks to Garvin Hicking)
  
• [BUGFIX] Allow replacing files with different mime-type and extension (thanks to Oliver Hader)
  
• [DOCS] Use better ReST markup for directory/filenames (thanks to David Bonhagen)
  
• [TASK] Update iso database (thanks to Anja Leichsenring)
  
• [BUGFIX] Use distinct XLF label for MIME-Type error message (thanks to Garvin Hicking)
  
• [BUGFIX] Avoid PHP bug when a link was not created via HtmlWorker (thanks to Benni Mack)
  
• [DOCS] Resolve rendering warnings in EXT:form documentation (thanks to linawolf)
  
• [DOCS] Migrate EXT:t3editor docs to guides.xml (thanks to linawolf)
  
• [DOCS] Migrate Changelog docs to guides.xml (thanks to linawolf)
  
• [BUGFIX] Fix runTest.sh rendering command (thanks to Garvin Hicking)
  
• [TASK] Add "runTests.sh -s checkRstRendering..." subcommands for docs (thanks to Garvin Hicking)
  
• [TASK] Update description of debugExceptionHandler (thanks to Stephan Großberndt)
  
• [BUGFIX] Ensure SuggestWizard's maxItemsInResultList to be an integer (thanks to Andreas Kienast)
  
• [BUGFIX] Improve allowed MIME type handling, add vcf handling (thanks to Garvin Hicking)
  
• [DOCS] Adjust indentation and headlines in EXT:lowlevel (thanks to Lina Wolf)
  
• [DOCS] Resolve rendering warnings EXT:lowlevel docs (thanks to Lina Wolf)
  
• [DOCS] Fix ReST warnings in documentation rendering (thanks to Garvin Hicking)
  
• [DOCS] Move "Extending the configuration module" (thanks to Lina Wolf)
  
• [BUGFIX] Add installation method to system information toolbar (thanks to Benjamin Franzke)
  
• [BUGFIX] Cleanup focusArea boxes when switching aspect ratio (thanks to Benjamin Franzke)
  
• [DOCS] Fix typos in form documentation (thanks to Chris Müller)
  
• [BUGFIX] Streamline type of buttons within backend button bar (thanks to Elias Häußler)