In the ESR68-based Tor Browser, Tor Launcher's custom bridge input field only allows one line of input. Some detective work reveals that Mozilla was in the process of removing XUL `textbox` during the ESR68 cycle and now it has been completely removed (for Firefox 71): https://bugzilla.mozilla.org/show_bug.cgi?id=1513325 They have switched everything to use `html:input` and `html:textarea` and we will need to do the same, eventually. Prior to ESR68, they removed support for multiline `textbox` elements, which is the cause of the custom bridge field breakage. We are working on a fix, although I guess it is too late for Tor Browser 9.0? I wish we would have noticed this sooner.