Last Zotero Firefox extension/addon release works great with Firefox ESR 52.3
I don't like to use the standalone Zotero 5, so I installed Firefox ESR 52.3 and the last Zotero Firefox extension release! :-)
https://www.zotero.org/support/4.0_changelog
Changes in 4.0.29.22 (August 9, 2017) - Released for Firefox only:
* Firefox 55 compatibility
Download URL:
http://download.zotero.org/extension/zotero-4.0.29.22.xpi
https://www.zotero.org/support/4.0_changelog
Changes in 4.0.29.22 (August 9, 2017) - Released for Firefox only:
* Firefox 55 compatibility
Download URL:
http://download.zotero.org/extension/zotero-4.0.29.22.xpi
I think it supprised many "Zotero Extension" (Firefox Addon) users, that Zotero decided to "upgrade" the Extension to the "Zotero Connector". After that the user will have no access to his Zotero Libary because the Zotero 5 standalone has not been installed with the upgrade to the Connector... As a result, there are many questions of confused Extension users in the forum.
2) When you first click the connector button after installation it explains the change, links to the blog post, and says to install the standalone app to access your data.
3) Zotero for Firefox and all other extensions based on the old Firefox extension framework will stop working in Firefox 57, so it's not like we have a choice here.