Allow for custom firmware usage, without forcing update popup on transaction

Hello there,

I have a project where a specific version of Trezor firmware needs to be used, because of compatibility with Metamask. A couple months ago I was able to have one of my devices with older firmware working fine for that purpose. However, for a while now, whenever I try to sign a transaction I get a pop up prompting me to update without being able to skip it. That enforcing of and update is quite unhandy. It would be great to have an option to go ahead with the signing, and skip the update at own risk. This is the pop up I refer to:

Many thanks.

that is because the MM is updated and it needs latest FW. You can try using older version of MM.