Incompatiable with Firefox 57

Firefox switched to a new way of making addons and makes this app unusable with the latest FF beta. https://support.mozilla.org/en-US/kb/firefox-add-technology-modernizing?as=u&utm_source=inproduct

[smichel17]

I remember seeing several duplicates of this issue with a lot of discussion in them, if you want to do a quick search.

[Dragnucs]

Please see #421, #410 and #396.

[alerque]

@Dragnucs None of those previous issues are relevant. @smichel17 Previous FF upgrades have each brought up various issues, but this one is completely different. The entire extension will need to be rebuilt from the ground up using the all-new WebExtensions API.

[smichel17]

#394?

[alerque]

@smichel17 That one is relevant for sure. In fact that should probably the canonical one for this issue and this one can be closed as a duplicate.