There are some know issues, and some I have observed:

1. Make sure you computer resources are not stretched to it's limit, you need memory for your browser to work on musing.io

aka. close your 20 tabs.

1. Some browser are more compatible than others, i find Chrome better than Brave for some reason, experiment and check

last but important note. save your unfinished respond from time to time, I do this: CTRL-A CTRL-C (select All, copy), then continue typing or editing. This is to save me grief it the browser session is lost, you don't want to lose that 5-25 minutes of your precious time you took to type a good and worthy answer.