bug#53452: 29.0.50; C-<arrow> selection broken by translate-upper-case-key-bindings

[Eli Zaretskii]

> Date: Sat, 22 Jan 2022 19:26:35 +0100
> From:  Ergus via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> When translate-upper-case-key-bindings is nil; the shift-arrow selection
> does not work
> 
> emacs -Q
> M-: (setq translate-upper-case-key-bindings nil)
> S-<right>  // says it is not bound... somehow expected.
> 
> M-: (keymap-global-set "S-<right>" #'right-char)
> S-<right>  // Now moves point but with no selection
> 
> I don't know where/how emacs recognizes the Shift in this case, but
> somehow it is not working

It sounds like it cannot work in that case, because shift-select
_requires_ that a key was shift-translated, and setting
translate-upper-case-key-bindings to nil disables that translation.