Exception in DrRacket (color.rkt)

[massung]

Several times now, playing around with 7.7/CS, I've gotten this in DrRacket:

reset-regions: got a region that is not a list of two numbers (or 'end if it is the last region): '(90 end), all regions '((90 end) (93 end))
  context...:
   do-error
   .../private/color.rkt:200:6: loop
   .../private/color.rkt:199:4: !reset-regions method in text-mixin

This is happening when I click "run", it launches a window and then when I close the window as I go back to DrRacket. It's highly inconsistent and quite sporadic (if it happens, then I run again it won't happen a second time). And I haven't noticed any pattern to what's causing it.

Note: I am not making a GUI application. I'm using my r-cade package to open a window, render, etc. But this happens on extremely simple programs that do next to nothing, and I've never had this issue on 7.6 (when I had 7.6, it was not the CS version).

I'm happy to help debug, just let me know what I can do.

Per request, mentioning @spdegabrielle.

[spdegabrielle]

@massung Please provide [ ] os details [ ] DrRacket configuration / plugins etc

[massung]

Windows 10 (v. 18362.778)

Re: configuration, I'm unsure what is wanted there. I have no external plugins installed. I'm using my own color theme (https://pkgs.racket-lang.org/package/dracula), and the only preferences modified outside of theme are in the tools and skipping a large number of them. Those skipped:

• Check Syntax
• DeinProgramm
• HtDP
• Macro Stepper
• RackUnit
• Repository Time Stamp
• Signatures
• Test Engine

[rfindler]

I'm not sure what is going on but judging from the error message, it looks like this is the likely culprit call:

https://github.com/racket/drracket/blob/master/drracket/drracket/private/rep.rkt#L1153