Fix download button

[ShadowRZ]

Description

Continuation of #1930, this time fix the download button.

Cinny uses file-saver to implment the download button, the file-saver implmentation has the following code:

https://github.com/eligrey/FileSaver.js/blob/5bb701bd6ea05a02836daf8ef88ec350a1dd4d83/src/FileSaver.js#L96-L98

which checks CORS using the following code:

https://github.com/eligrey/FileSaver.js/blob/5bb701bd6ea05a02836daf8ef88ec350a1dd4d83/src/FileSaver.js#L47-L55

In the earlier implmentation, HEAD request wasn't hooked, so when file-saver saves a file, it'll believe CORS request failed and try to open the URL in the browser tab, which won't work at all with authenicated media endpoints.

By hooking HEAD requests too, file-saver would properly save this file without opening a new tab.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings

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[ajbura]

I reviewed it, and it looks like file-saver still open them in new tab with /media/download url which is out of the scope of our service worker. so maybe a good fix will be if we change file-saver usage with custom download login?

[ShadowRZ]

Probably, yes. Maybe telling file-saver to download a blob is better.

[kfiven]

Closing in favour of #1947