[KevinH]

Drag and drop in the editor was never officially supported because its usage constantly caused Qt segfaults. Its use is disabled for that reason as we do not want to support something that can cause crashes that we can not fix as they are internal to Qt.

There is an environment variable a user can set to re-enable it in Sigil. But if you choose to do that, you will get no support from us for any crashes it may cause.

I do not remember the exact env variable name anymore, but it is documented in the advanced chapters in our Sigil user guide that deals with environment variables and Sigil.

Update ... Found it:

SIGIL_ALLOW_CODEVIEW_DROP If this value is set, drag and drop editing inside CodeView is enabled. Be warned that on some platforms, using drag and drop to edit inside CodeView can be unstable causing Sigil to crash. No support will be provided to people who decide to enable drag and drop as fixing these issues are outside our control (internal to Qt6).