Thank you for sharing, sounds very interesting!
That people can easier find this later, would just rename the title to include more keywords, perhaps something like...
video-plugins / mp4: Howto UPDATE to latest versions of the LAV-Filters
Quote
NKU
How to use the latest versions of the LAVFilters:
1) delete the current version of the lav-files in directory k-meleon (avcodec-lav-57.dll, avresample-lav-3.dll, avutil-lav-55.dll).
2) open file "xul.dll" in directory k-meleon with a text editor (such as notepad++). Replace "avcodec-lav-57" with "avcodec-lav-58" and "avutil-lav-55" with "avutil-lav-56".
3) download the current version of the LAVFilters (github.com/3dyd/LAVFiltersXP/releases/download/0.74.1.9/LAVFiltersXP-0.74.1.9-x86.zip - for WinXP, github.com/Nevcairiel/LAVFilters/releases/download/0.75/LAVFilters-0.75-x86.zip - for Windows Vista or newer) and extract files "avcodec-lav-58.dll, avresample-lav-4.dll, avutil-lav-56.dll" to the directory k-meleon.
Do not use LAVFiltersXP on Windows Vista or newer, this causes the browser to crash.