Firefox Add-On Does Not Work
Installed and shows correctly under extensions and is enabled. Todoist button also appears on Firefox v16.0.02.
When button is pressed, left pain opens but is completely blank. There are no options or anything - just a pane "header" that says TODOIST. No way to use the function, but I can access the website to work on my project lists.
Please log out, clear your browser's cache and offline storage data. Then, in Firefox's Options -> Privacy, make choose "Custom settings for history" and make sure that all cookies incl. third-party cookies are accepted. After reloading the browser, try to open the plugin pane again.
Sorry to say that I am able to complete all the steps you recommend except I cannot log out. The log out option is not available on any screen I see on your website.
Moreover, I just now installed a the Firefox add-on on a different computer as a test. On that computer, I was not logged into todoist.com. I also cleared cache and verified the custom privacy options you directed. However, the same problem (blank plugin screen). Then, logged into the todoist site with the goal of then logging out. However, again no log out screen.
In order to log out, please click on the gear icon in the upper-right corner and choose "Logout".
I've just tried to use the Firefox add-on again and it's still working on Firefox 16.0.2 so unfortunately I can't reproduce this issue.
If you're clearing the complete cache incl. offline data (removing todoist.com from the list of sites storing offline data in Options -> Advanced -> Network), are accepting third-party cookies and the plugin doesn't work (it make take a short while for it to load your tasks, depending on the number of tasks you have), then please try to disable every other plugin in your browser and see if it helps.
I've now tried this on 3 PCs. All exhibit the same behavior, including one where all non-critical Firefox extensions were disabled.
Cannot invest any more time in a problematic time-management application.