TYPO3 Core

Steps to reproduce:
- Upload a file in the filelist
- Check filename of preview image (e.g.: preview_102455_4635_924f2e40ad.jpg)
- Overwrite with a file with the same filename but different file content
- Check preview filename again --> it stays the same
--> We've seen caching issues with IE9 because of this

As a workaround we added the following config in the .htaccess file:

<FilesMatch "^preview_.*\.(jpe?g|png|gif)$">
  FileETag none
  <ifModule mod_headers.c>
    Header unset ETag
    Header set Cache-Control "max-age=0, no-cache, no-store, must-revalidate" 
    Header set Pragma "no-cache" 
    Header set Expires "Wed, 11 Jan 1984 05:00:00 GMT" 
  </ifModule>
</FilesMatch>

This worked for the filelist: we now see the correct preview image directly after overwriting without manual browser reload or browser cache clearing.
BUT: In the list or page module we still see the old preview image until the IE9 tab has been reloaded (without the .htaccess rule we had to clear the browser cache to see the updated preview image). Of course this all works flawlessly with FF :)