Duplicate MUC messages

[COM8]

Bevor you create a new issue:

- [ x ] I searched for similar issues and did not find one
- [ x ] I'm using the latest version available in the [Windows Store](https://www.microsoft.com/store/apps/9NW16X9JB5WV)

I'm submitting a...:

• Bug report (I searched for similar issues and did not find one)

Current behavior:

Duplicate MUC messages on reconnect for MUCs hosted by jabb.im.
Looks like they use their own server software.

Expected behavior:

No duplicate messages

Environment:

App Version(s): 
v.0.10.0 <!-- Which version of the App are you using (e.g. v.0.2.0) -->

Device form factor:
- [ x ] Desktop
- [ x ] Mobile
- [ ] Xbox
- [ ] Surface Hub

Where did you got the APP from?
- [ x ] [Windows Store](https://www.microsoft.com/store/apps/9NW16X9JB5WV)
- [ ] Self-build, using a provided release source
- [ ] Self-build, repo cloned at [dd.mm.yyy] <!-- When did you clone the repo! -->
- [ ] Misc, got it from... <!-- Please tell us your source! -->

[COM8]

Can not reproduce it.

[COM8]

Will close this since I can not reproduce it.