Test with this bookmarks.html:

<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Bookmarks</title> </head> <body> <dl> <dt><a href="https://www.example.com">Example Domain</a></dt> <dt><a href="https://www.arstechnica.com/">Ars Technica</a></dt> </dl> </body> </html>

Does that at least import without crashing/freezing?