Mac Users Should Not Upgrade to High Sierra Yet
Apple has released an update that addresses the cursor problem described in this post. For details, see this post by Steve Werner.
Important news: macOS 10.13, aka High Sierra is out, but InDesign users should hold off on upgrading because there is a significant bug that will cause problems with the cursor in InDesign and Illustrator. Adobe has published a list of known issues with High Sierra for both Illustrator and InDesign.
You can see screenshots of the cursor problem in InDesign at this post on the Adobe forums. It ain’t pretty. The last time I saw a cursor like that I had to pull the cartridge out of my Atari 2600 and blow on it. Unfortunately, this time, there is no such simple fix.
In fact, at this time there is no fix at all, other than reverting back to Sierra (good luck), or switching to Windows ;)
According to reports, you can temporarily make the cursor problem go away by restarting InDesign. But it will eventually come back. Caveat upgrador.