When you say it doesn’t work in Firefox, does it not work in Firefox or does it say it doesn’t work in Firefox? In the later case and sometimes in both, I have found that just changing the user agent string to something chrome based is sufficient to get it working again.

Anyone know how to convert the flipper code format into the base64 format that home assistant/broadlink uses?

Examples of format https://community.home-assistant.io/t/broadlink-remote-send-command/286215