Great work on the Thunderbird rebuild so far. Loving the work that has gone into this already. Some major improvements already being seen here. Well done! My only gripe is with the message menu bar - specifically in relation to bulk message handling options.
In the previous version of Thunderbird (102 I believe I had) there was the means to customise the message bar with quick actions such as 'mark all as read' when selecting multiple messages in the list. In the current beta, this seems to have been removed and is only accessible when either right-clicking the multi-selection in the main list window or when selecting the 'More ∨' context menu and toggling "mark as read/unread".
What I would like to see available, is the means to add these functions, specifically the mark all as read/unread toggle as a button on the message bar when selecting mutliple messages. Laziness I know, but it makes it simpler if I can select all the messages I want, and then simply click the button toggle, rather than having to go through the right-click context menus instead.
Hoping it can be considered to greatly improve on bulk message handling options when selecting multiple messages at once.
See attached screenshot for reference.