Component returned failure code: 0x80004005 (NS_ERROR_FAILURE)

[jeffsilverm]

While looking at issue 69, I get a very similar but slightly different error message. I am running bluegriffon 3.1.2 on Ubuntu Linux 20.04. My error message is:

[Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE)
 [nsIEditor.deleteNode]"  nsresult: "0x80004005 (NS_ERROR_FAILURE)"  location: "JS frame :: 
chrome://bluegriffon/content/js/bluegriffon.js :: CloneElementContents :: line 2183"  data: no]

I can save the file if I am in source mode. If I close the file and reopen it, or if I close the file, exit from BG, start BG, open any file, then many menu items are grayed out, including but limited to copy, cut, paste, find...

FWIW, I see that Daniel Glazman (:glazou) made a comment in Mozilla's bugzilla: Add-ons manager view-port is blank when opened in a standalone window, which might or might not be relevant.

I tried:

jeffs@jeffs-desktop:~/logbooks$ fgrep -r bluegriffon.js /opt/bluegriffon/
Binary file /opt/bluegriffon/chrome/bluegriffon.jar matches
Binary file /opt/bluegriffon/chrome/responsive.jar matches
jeffs@jeffs-desktop:~/logbooks$ 

I tried investigating the contents of these jar files with the jar -t -f command, but it refused to work on them.