No longer works for me in Firefox (running on Linux). For several WEEKS, clicking on ico asks for login, goes to web site, logs in... then clicking on again icon will *very* briefly display the working menu, but that is quickly replace by a login prompt. This will repeat forever. The extension never understands that I have logged on. The product is now useless for me. EDIT - The problem seemed to be a conflict with the add-on "First Party Isolation." I disabled that and I can now log on. The Evernote add-on seemed to have a problem with First Party Isolation too. But not of my other add-ons.