waitForFont adds ~5 second delay

Noticed my diagrams were rendering very slowly. It appears that waitForFont takes time to load even if it's not doing any loading. I've just disabled it in my local version of the code but it might make sense to make it a configuration option if people don't want to incur the delay?

Start by locating the waitForFont implementation and tracing why it waits when no font loading is needed. Confirm the roughly five-second delay while rendering diagrams, then determine how the requested opt-out configuration should affect that behavior; the issue names no specific test or file to run.

Written by the indexing model from the issue text.