1728293 - F6 jump focus handler is inconsistent for the message tab

Status: NEW

(Thunderbird :: Mail Window Front End, defect)

Description

[Henry Wilkes (they/them) [:henry-x]]

Steps to Reproduce

1. Launch Thunderbird.
2. Either do nothing and keep the focus on the initial tabmail-tab, or move focus to the top #tabs-toolbar, the toolbar #mail-bar3, the #folderPaneHeader, or the Today pane #agenda-panel.
3. Press F6 twice.
4. Tab incrementally into the Folder tree, or select with mouse to focus it.
5. Press F6 three times.

Result

In step 3, focus moves between the main tabmail-tab and the messagepane.
In step 5, focus moves between the #folderTree, #threadTree and #messagepane.

Note, similar things happen when pressing Shift+F6, which just reverses the direction.

Expect

The behaviour should be more consistent:

• The #folderPaneHeader should be treated as the same area as #folderTree, so pressing F6 in either place should move the focus in the same way.
• The behaviour of pressing F6 from the #messagepane shouldn't depend on how the area was entered.

Possible Solution

My idea would be to section the main areas of the message area as:

1. The tabs.
2. The toolbar (or merge into the same area as the tabs).
3. The folder area (#folderPaneHeader and #folderTree) if visible.
4. The thread tree.
5. The message display if visible.
6. The Today Pane if visible.
7. The status bar if visible (which currently does not recive focus through normal tabbing)

And F6 should cycle through these in this order all the time. If some areas should be excluded from this list, then F6 should do nothing when within those areas.

The function to fix would be SwitchPaneFocus.

Comment 1

[Henry Wilkes (they/them) [:henry-x]]

Another note: since the main tab cannot be closed, there isn't much use in being able to focus it. So I wouldn't mind excluding the tab altogether from the jump focus cycling. But it might still be good to include the toolbar (and focus the first visible toolbar item when we jump there). And, it might make sense to change the initial start up focus from the tab to some element within this main cycle.