Add extension to filename automatically

[kohanyirobert]

Would you consider adding such a feature?

• The dropdown would appear only if in the settings one enables "override extension" or something
• The "override extension" setting is only active if one enables the "override filename" option
• When not enabled everything looks and works right now, if I specify a filename as "the filename" it'll downloaded as such (without extension)
• When enabled it defaults to something like "default" (in the dropdown), which would mean adding %(ext)s to the end of the --output template, otherwise it can be prepopulated with popular options (mp4, mkv, mp3, webm`)
• Optionally if the "override/select format" option is disabled it could populated with available options
• When I download something with the new option enabled and selected the "default" option it'd add the extension to the end of filename (e.g. 'the filenamebecomes 'the filename.mp4' if that's the extensionyt-dlp` determined suitable

What do you think?

[marcopiovanello]

To me it can be implemented. It doesn't change much on both on the backend and frontend.

It will also solve opus audio saved as webm (even if it's technically correct)

[kohanyirobert]

Cool. I saw that you're in the middle of choosing another UI framework for the project. How's that going? I'm okay with shipping this change in a PR with the current UI (it looks okay by me), but only if you're willing to merge, lol. What do you think?

[marcopiovanello]

The next frontend will be with shadcn (not a crazy fan of that library but that's what the community has chosen 😃).

I'm going to start working on it by the next week.

The extension feature will come before the UI rework.