Leaving and rejoining a community causes failures

[holmesworcester]

Steps to reproduce:

Leaving a community and rejoining multiple times causes predictable failures.

[holmesworcester]

Notes from Wiktor:

• If the failure is on mobile only, it may make sense to first look at how the mobile app stores redux state

[holmesworcester]

Note: wait until @leblowl merges his latest work before picking this up. Assigning to him until he merges.

[kingalg]

2.2.0-alpha.7 [email protected] | iOS 376

Fixed. Checked on all supported systems.