Hi Phillip and Koen,
Please refer to our latest reply.
An update to the Insider Fast channel version 16.16 (180625) has fixed the issue. This fix will slowly trickle down to other channels (Insider Slow as well as Production).
If you would like to get this release early, you can join the Insider Fast program by referring to the article below:
Office Insider - Mac
Jim has also mentioned that for those unwilling to use pre-beta software (Insider Fast) you can use Insider Slow. Insider Slow delivers the upcoming release a little sooner than waiting for it to come through the regular
update; however, please note that we do not have an ETA for the release.
Update on 7/5: A newly released build of Insider Slow version 16.15 (0701) has the fix. You can download that instead of Insider Fast.
To let other community members easily see the information, we will be locking this thread from further posting. Once the fix has been deployed to the Insider Slow and Production build, we wil let you know.
Regards,
Sheen