Restarting Firefox looses local E2E encryption keys

[schmittlauch]

Description

I'm sure this is a duplicate of some issue, but I just couldn't find a relevant one so far.

Whenever I restart my Firefox, I am not able to decrypt previous messages from E2E rooms I wrote or which were sent to me, because apparently the local keys got lost.

I set up Firefox to purge cookies at restart, but not "offline website data" (which I think should be LocalStorage). So I expect the keys to remain between browser sessions.

Steps to reproduce

• start an E2E conversation
• exchange messages with communication partner
• restart Firefox (in my case without logging out, don't know if that'd make a difference)
• log in again because session cookies have been purged
• see that messages from the past can't be decrypted anymore due to missing key

Log: not sent

Version information

• Platform: web (in-browser)

• Browser: Firefox 59.0.2

  • special settings: about:preferences#privacy set up to clear Cache, Cookies and History when closing Firefox

• OS: Gentoo Linux amd64

• URL: riot.im/app

[dbkr]

If you're getting logged out, it's because your localstorage is being deleted. To be honest, I couldn't tell you what exactly Firefox means by, "Offline website data". It seems Firefox itself isn't entirely sure (https://bugzilla.mozilla.org/show_bug.cgi?id=1047098). In this case, localstorage is presumably included as part of 'cookies'.