Qt Creator unresponsive and scales incorrectly on MacOS 10.14.4 Beta 18E215a

After updating to MacOS developer beta 10.14.4 (18E215a), Qt Creator 4.8.2 does not work properly. I'm seeing the following issues:

• The interface is largely unresponsive; none of the buttons in the main window after launching Creator do anything.
• Attempts to resize the window cause the content to stretch rather than reflow.

I've attempted to upload a screenshot of the latter but it says "Jira could not attach the file as there was a missing token. Please try attaching the file again." Here's an imgur link instead:

https://imgur.com/a/MH03mWJ

Detailed Qt Creator version info

Qt Creator 4.8.2
Based on Qt 5.12.1 (Clang 10.0 (Apple), 64 bit)
Built on Feb 28 2019 16:15:13
From revision 04aac85e26