Dynamics App for Outlook flickers in OWA and set Regarding is impossible

Question

Hi there,

Some of my users experience a flickering App for Outlook screen when they want to 'Set Regarding' on an appointment (connecting to a project or salesopportunity in Dynamics). The app/pane opens, you can scroll through the menu and pick an item, then pick the record you want to track but then the 'Dynamics 365 pane' starts to flicker and there is no way you can click on 'set regarding'.

One of them told me today that it stopped flickering upon changing the screensize (browser from full screen to smaller).

I have also noticed that in some cases the Dynamics 365 pane appears double on the screen?

Although I tried to exclude certain circumstances I cannot put my finger on it:

I cannot reproduce the issue (tried 2 different accounts)

It happens on windows and mac machines

and it looks like it's only happening in OWA

Last week clearing cache didn't solve the issue, using another browser did, but not this week...

Does anyone have any suggestions?