Review for Reply to All as Cc by Gabriel
Rated 5 out of 5 stars
There's a very simple fix to enable this addon in Thundebird 60:
1. Set extensions.strictCompatibility to false
2. Open <profile path>/extensions/reply-to-all-as-cc@clear-code.com/content/composeOverlay.js
3. Replace 'listitem' with 'richlistitem' in line 43
4. Restart Thunderbird
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