The latest version of WordPress changed some CSS in Gutenberg, so the Content Converter UI is now broken — we get a blue screen instead.
However for now until we fix the Converter, we can still use and run the Converter this way:
run Converter as usual, instead of the UI showing progress, when the conversion starts and you see a blue screen in Editor area, open the Console, and monitor the progress
everything will work as usual, except the UI is not visible until we fix it
thomasguillot
commented
3 years ago
The latest version of WordPress changed some CSS in Gutenberg, so the Content Converter UI is now broken — we get a blue screen instead.
However for now until we fix the Converter, we can still use and run the Converter this way: