Summary
Latest version of https://sandbox.kie.org/#/ say it is not compatible with firefox browser.
This ticket is a request to support it. Originally this was allowed and no modal was displayed to user. Now it is fully disabled.
For future reference and possible investigations needed to enable fireforx support se this PR introduced the change - KOGITO-7826 - https://github.com/kiegroup/kie-tools/pull/1244

Goal
Support Firefox ESR releases.

Non-goals
Introduce it-tests running on firefox

AC
Firefox is a browser where KIE sandbox can be run.