panel fails to open after context menu use in some cases

I'm not exactly sure what's causing this but I was able to isolate a repro:

1. go to https://codepen.io/argyleink/pen/dPGBYZg
2. click the color to open the color-input panel
3. right click on the color-input panel itself to open the browser context menu
4. click outside the context menu to close it
5. click outside the color-input panel to close it

Expected: the panel closes and can be opened again by clicking the color again.

Actual:
* Chrome: the panel closes but the button no longer opens the panel
* Firefox/Safari: the panel does not close unless the user clicks a 2nd time, but then the button works to open the panel again

Start with the color-input panel and its open/close event handling, using the CodePen reproduction in the issue to compare Chrome, Firefox, and Safari. Reproduce the context-menu sequence, then trace the panel and button state after the context menu closes; done means the panel closes normally and the color button reopens it consistently in all reported browsers.

Written by the indexing model from the issue text.