Bug reports this way please ---> https://github.com/xternal7/ultrawidify/issues

Take care to include browser version, OS, monitor resolution, other extensions.

Potentially also screenshots because I don't know what the hell you mean with 'doesn't crop properly'. "Fit to width" should crop perfectly if you're watching 21:9 content encoded in non-21:9 aspect ratio on a 21:9 monitor.

And if you have a monitor with aspect ratio wider than 21:9 (this one Samsung), you should use 'Force aspect ratio' option for proper letterbox removal.

(Also please note I'm currently on hiatus due to some personal issues. If all goes well, I'll be able to continue with October)


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EDIT: I think I might have randomly stumbled over the "doesn't crop properly" instance. There's this trailer for Salt that's 16:9 + letterbox, but the video isn't 21:9. This leads to extension cropping away too much:

https://www.youtube.com/watch?v=QZ40WlshNwU

Which is why there's zoom/unzoom binds.

Automatic aspect ratio was impossible(-ish)¹ a year ago. It's still impossible-ish¹ now.

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¹It's actually within the realm of theoretical possibility, but whether that's gonna work with Youtube is unclear until I test it. There's also further potential complication with attempting auto-aspect ratio on youtube, vaguely outlined under this review:

https://addons.mozilla.org/en-US/firefox/addon/ultrawidify/reviews/829521/

TL;DR: potential performance issues.

Inb4 "but it can be done on netflix" — Netflix aspect ratio "autodetection" isn't true autodetection and is only possible because IMDB generally posts aspect ratio of every movie it knows.