Multi-select in conversation

[lgrahl]

Being able to select multiple messages would enable...

• downloading multiple files/images at once, and
• removing multiple messages at once.

The technical challenge for multiple downloads is the amount of dialogs popping up (one for each image/file). It could be bundled into a zip file by the web client or by the app.

Would highly benefit from a way to stream the download to disk instead of buffering it into memory.

Originally requested here: https://threema-forum.de/thread-4117-post-40500.html#pid40500

[dbrgn]

I long thought about this, but could not figure out a UI that would work well.

Maybe as part of a media gallery (#212)?

Bundling the downloads will be tricky though.