EDIT: Consider improving some wordings in the list of keyboard shortcuts for Thunderbird

[rtanglao]

• EDIT: https://support.mozilla.org/en-US/kb/keyboard-shortcuts-thunderbird
• Based on bug 1712638, Consider improving some wordings in the list of keyboard shortcuts for Thunderbird

ThomasD's 3 year old relevant comment from bug 1712638 still seems relevant

Hello Marja, thanks for your feedback.

(In reply to MarjaE from comment #0)

Many of the instructions are wrong.

Well, if 4 out of more than 150 shortcuts were wrong, that's probably not so many...
I really know because some years back, I completely redesigned and updated this document...

    It states that F goes to the next message. It only does this in the message list. If I open 
    a message in a new tab to read it, read it, and type F, Thunderbird opens a find popup 
    at the bottom of the window.
    It states that B goes to the previous message. It only does this in the message list. If I open
    a message in a new tab to read it, read it, and type B, Thunderbird opens a find popup at the
    bottom of the window.

Worksforme on Win10, 91.5.0 (64-bit).

open message 2 in tab
press F -> message 3 shown in the same tab
press B, B -> message 1 shown in the tab

Pls try ≡ > Help > Restart with Addons Disabled….
If it still fails for you, please file a bug against Thunderbird (we can't use this one because it's against documentation).

    It states that Tab "Move[s] to Next UI Element". Of course if it does move, then it 
    moves to what would be the next place it moves.
    It states that Shift + Tab "Move[s] to Previous UI Element". It does not. Create a 
    new tab, move to the new tab, Shift + Tab does not move to the previous tab. 
    Return to the main tab. Move to a new folder, Shift + Tab does not return to 
    the previous folder.

Well, I am not seeing anything actually wrong in the documentation here - but I understand you're not happy with the wording. Can you propose a better wording? Please note the criteria for the new wording:

short
preferably action-oriented (with a verb)
simple language (preferably non-technical)
correctness
consistency with other items where applicable

I've tried, but struggled to find a better wording... More precision here probably comes at a price of being either more technical or clumsier. Maybe this?

Focus the next element in the tab order - Tab
Focus the previous element in the tab order - Shift+Tab

Please note: We have three different ways of moving focus:

regular: [Shift+] Tab moves along the regular, mostly implicitly focusable 
tab stops. Due to the residues of XUL in our User interface, not every UI 
element is included; other elements are deliberately excluded (see next point).
fine/unlimited: Ideally, when there are unlimited elements in a container, tab 
should just have a single stop on the container, and internal navigation should 
use cursor keys. Recipient pills in composition are a good example; Recipients 
in message reader of TB 91 are the bad example.
fast: [Ctrl+][Shift+] F6 moves along a few hand-picked main tab stops 
(aka fast focus cycle)

Tab is unpredictable especially since Thunderbird doesn't show focus,

Tab is quite predictable for me (on Windows at least), and usually shows focus, but it does go into hiding sometimes. Which would be a bug, but imo it does not affect the accuracy of the documentation. If you have specific fails, please file bugs against Thunderbird.

but Shift + Tab seems to return to the next-higher UI element, rather than the previous UI element.

That's the wording thing again, not really wrong, but maybe we can find something better. Next-higher doesn't sound natural, whereas previous sounds quite applicable to me. We're not saying adjacent or previous in your focus history. Previous means: Previous in the "tab order", i.e. the predefined, circular sequence of "tab stops" (and again I'm not sure if tab stop is a good and appropriate term or not).