Have you reported issues for them? It’s in the menu somewhere. If Mozilla get a lot of reports for particular sites, they reach out to the webmaster and try to work with them to improve Firefox support - usually by removing proprietary Chrome-only features or by removing reliance on Chrome bugs that don’t exist in Firefox.
You can also report the issue at https://webcompat.com/, just search to see if it’s already been reported first.
Have you reported issues for them? It’s in the menu somewhere. If Mozilla get a lot of reports for particular sites, they reach out to the webmaster and try to work with them to improve Firefox support - usually by removing proprietary Chrome-only features or by removing reliance on Chrome bugs that don’t exist in Firefox.
You can also report the issue at https://webcompat.com/, just search to see if it’s already been reported first.