I just want to share this workaround other users including myself have noticed for a particular prevalent and recurring issue.
Pretty much a couple of the mainstream distributions have been reported about the same issue on this forum, but it still occurs for the “ready-to-run” bundle even when users attempt to resort to working with it.
There may be unintended differences, and even bugs in Ubuntu native packages, as a result of a different building method. For this reason, Ardour developers highly recommend installing the official ready-to-run version of the program that can be downloaded from ardour.org, as Ubuntu native packages are not supported in the official Ardour forums or other support channels.
Distro-specific support is not encouraged on this forum so I focus the fix-workaround towards the path as is used by the ready-to-run bundle.
cd /opt/Ardour-5.12.0/lib mv libfontconfig.so.1 libfontconfig.so.1.backup
Basically just rename libfontconfig.so.1 and that tends to solve the monospace font and long startup issue. It’s quick and simple …
hope this helps.