Missing parts in the timeline

[HarHarLinks]

Steps to reproduce

Not entirely clear how this happens yet, but I think this is a pretty severe issue.

1. Use Element Desktop for a day
2. Next day, use Element again, possibly from a different session like phone or another computer

Outcome

What did you expect?

Timeline is complete

What happened instead?

Some messages are missing from the timeline, including some I sent myself from the same session.
Can be worked around be restarting Element.

Operating system

arch, win 10

Application version

Element Nightly version: 2022061501 Olm version: 3.2.8 (arch), stable 1.10.15 (win 10)

How did you install the app?

aur, element.io

Homeserver

synapse 1.60.0

Will you send logs?

Yes

[HarHarLinks]

same with synapse 1.61.0

[lub]

I see the same with Synapse 1.59.1

It seems it also breaks the encryption, because after restarting Element I see the previously missing events in the timeline but only with "** Unable to decrypt: The sender's device has not sent us the keys for this message. **"

Messages sent while the timeline was incomplete also seem to be just lost after refreshing the website/restarting Element.

[HarHarLinks]

All but one room where I noticed that were encrypted and not federated, but I did not have any "Unable to decrypt" type of problem.

Edit: classic speak of the devil moment. This time I'm getting the situation described by lub. Element version: 1.10.15 on W10

Edit 2: Today I got a stuck notification dot along with it. Element Nightly version: 2022061501 on Arch

[HarHarLinks]

I haven't seen this in a while, maybe due to using only a single E desktop instance during this time. However I have been using E android (particularly the schildi fork), and my own messages tend to have gray shields despite being xsigned.