Hello,

I'm Xiaoyu Liu, a chimera user. Thank you for developing and sharing this powerful software. I have a problem now and bothered me for a while when using chimera. I'm wondering if you know how to solve it.

I downloaded chimera-1.15-mac64.dmg from "https://www.cgl.ucsf.edu/chimera/download.html" for  my Mac OS Catalina(10.15.5). When I rotate the molecule with left mouse button, an extra character "c" will be automatically added in command line. Each rotation will result in adding one "c". Here I have some screen shot to show more clearly.
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I tried to restart my computer. It is helpful within the first 10 minutes after the restart, but later it has the problem again. Please let me know if you know how to solve it. Many thanks!

Best,
Xiaoyu