Understanding Emacs errors

from blog Oliver Caldwell's blog, | ↗ original
You can probably begin to get to the bottom of most internal Emacs problems with debug-on-entry. This function prompts for a function name interactively (which also hooks into helm) and will essentially set a breakpoint within Emacs on that function. When it is called you’ll get to see what functions were called and with what arguments. This came...