Arrows at left of Subject column (left arrows and right arrows): What do they mean?
(These are curved arrows.) They may have to do with the chain of correspondence. Placing the cursor over the arrows does not provide any more information. Nor does searching the Support history in Mozilla Support.
被選擇的解決方法
These arrows are refering to whether you have replied and forwarded the email.
Whilst a few icons have been modified over the years, many are still the same as the info : http://kb.mozillazine.org/Icons_-_Thunderbird_2
從原來的回覆中察看解決方案 👍 0所有回覆 (2)
The left arrows are red and the right arrows are blue. (Something went wrong and this important information was left out of my original question.) (Mozilla would not allow me to edit the question!)
選擇的解決方法
These arrows are refering to whether you have replied and forwarded the email.
Whilst a few icons have been modified over the years, many are still the same as the info : http://kb.mozillazine.org/Icons_-_Thunderbird_2