VLSub unable to load some Subtitles with ssa file type and *.ass file extension

Some Subtitle files of the type .ssa have the filename extension .ass and cant be loaded by VLSub, for example:

"[CR] Beast Tamer S01E07 The Captive Fairy.en-US.ass.gz"

The function find_subtitle_in_archive() gets passed item.SubFormat, which in this particular case is ".ssa". Since .ssa != .ass, the function fails.

I added some debug messages to my VLSub.lua locally to figure this out:

[00007f797c28bec0] lua generic debug: [VLSub] find_subtitle_in_archive subfileExt: .ssa
[00007f797c28bec0] lua generic debug: [VLSub] item: file:///home/user/.cache/vlc/%5BCR%5D%20Beast%20Tamer%20S01E07%20The%20Captive%20Fairy.en-US.ass.gz#!/beast.tamer.the.captive.fairy.(9309068).nfo
[00007f797c28bec0] lua generic debug: [VLSub] extension: .nfo
[00007f797c28bec0] lua generic debug: [VLSub] item: file:///home/user/.cache/vlc/%5BCR%5D%20Beast%20Tamer%20S01E07%20The%20Captive%20Fairy.en-US.ass.gz#!/%5bCR%5d%20Beast%20Tamer%20S01E07%20The%20Captive%20Fairy.en-US.ass
[00007f797c28bec0] lua generic debug: [VLSub] extension: .ass