From: Thomas Bachem <mail@thomasbachem.com>

Since 128914438a (sideband: add options to allow more control
sequences to be passed through, 2026-03-05), the value of
sideband.allowControlCharacters is a comma-separated list of
keywords. When the parser meets a keyword it does not know, it warns
but stays on that keyword, so the warning repeats forever.

As the setting is read whenever a transport is set up, a typo like
"colour", a list written as "color, cursor" with a space, or a
keyword that only a newer version of Git knows is enough to make
every fetch, push, clone and ls-remote hang this way.

Move on to the next keyword after the warning, and name only the
unrecognized keyword in it, not the rest of the list.

Assisted-by: Claude Opus 5.5
Signed-off-by: Thomas Bachem <mail@thomasbachem.com>

Submitted-As: https://lore.kernel.org/git/pull.2261.git.1792154374653.gitgitgadget@gmail.com