I figured out how to reproduce this issue consistently on my machine:
1. Type something, anything, a few characters to give your cursor some room to move. 2. Find your blinking input cursor, probably at the end of the line 3. Move your mouse directly over the blinking end-line cursor, it has to be pixel-perfect lined up 4. Click and hold, now drag your mouse elsewhere, it should look like it's highlighting 1 char-width blocks where text is present 5. Let go, crash, and profit... or not :D
To prevent crashing:
If you click and drag, and notice that you are highlighting single characters, drag all the way up to the title bar, off the actual text entry area, then let go, that should prevent the crash. It may work if you drag anywhere outside of the text area and let go, not sure.
This has been driving me bat-shit-crazy the last week or so, I don't know exactly when it started happening. The issue was present in an earlier build, but instead of crashing, it would scroll you to the top. Now it crashes.
Let me know if you guys can reproduce the same way I can... curious to know.