Make FilePanel work with e2e crypto

[ara4n]

We should extend the indexeddb stuff to let locally referenced attachments show up in FilePanel.

See also #2591

[ylecollen]

Done on the android client.

[ara4n]

as #3679 shows, this is a bit surprising - i'd expect the e2e contents to be decryptable in the sidepanel if they can be decrypted in the main panel!

[thoraj]

Is this deemed a wontfix?
With e2ee enabled by default perhaps this should be addressed?

[turt2live]

It's on the list of things to improve now that we have e2e by default. Anything we don't plan on fixing is closed.

[t3chguy]

Am confused, we have this now powered by Seshat in riot-desktop. What's there to improve?

[aaronraimist]

Both filepanel and search need some kind of warning in Riot Web that nothing came up because you aren't using Riot Desktop.

[t3chguy]

Sure, keeping in mind that rooms don't always start off encrypted so the plaintext ones still can exist and be shown

[aaronraimist]

Right but if the room is encrypted there should be a warning below any unencrypted items saying something along the lines of "There may be more files but Riot can't find them because..."

[thoraj]

I'm a bit confused.

Isn't this issue about getting the FilePanel to show links to all files (rather than showing a notice about possibly missing files?)

After all, the main message area can show the links, so I think users will be surprised if files may be missing in the FilePanel?

[t3chguy]

Isn't this issue about getting the FilePanel to show links to all files (rather than showing a notice about possibly missing files?)

This is already done in riot-desktop using Seshat as stated above. On riot-web it'd be a very expensive operation which might literally not be done and instead an explanation of why its infeasible and a link to riot-desktop might be provided instead.,

[kittykat]

What are the acceptance criteria for this task being resolved? I have two related problems, but I'm not sure if this task covers them:

1. element-web does not show me encrypted files in the FilePanel, but it does tell me to go use the desktop app (as mentioned above).

2. The desktop app does not show me files for some encrypted rooms (I don't know when the encryption was enabled, but I suspect on room creation as it's now the default and the room is recent). The room's files menu not showing anything  #15318 could be a duplicate. Desktop app on left, web to the right:
   

These same images show up in the right place on Android:

[ara4n]

The desktop app should in theory support FilePanel in E2EE rooms these days. If it's not working there on some rooms, let's open a new bug to track it.