Thanks for reporting this. We are in the process of fixing this.
For the curious: the internal browser of Studio Pro (Chromium Embedded Framework) was upgraded in 8.1 and this causes a memory leak under certain, still unknown, conditions. We are going back to the previous version for now.
Hopefully you’ll have an 8.1.1 on Monday. Fingers crossed.
Update: Mendix 8.1.1 has been released. See https://docs.mendix.com/releasenotes/studio-pro/8.1#811
That is a known bug. See the release notes for 8.1: https://docs.mendix.com/releasenotes/studio-pro/8.1#810
Regards,
Ronald
Please file a ticket for this issue.