KWin sends the `failed` reason on zkde_screencast localized. The retry
short-circuit matched the English "could not find output", so a pt-BR session
("Não foi possível encontrar saída") fell through to 8 attempts over ~11 s and
then reported "out of retries" — a config fact dressed up as a flaky one.
Match "KWin virtual output failed" instead: our own prefix, never translated.
Every `failed` KWin sends on this path is a backend/config fact (unsupported
compositing type, a backend without createVirtualOutput, an output the
workspace declined to enable), none of which a retry 500 ms later changes.
The message itself now says what KWin's untranslatable reason means, and the
KDE docs gain the KWin 6.6+ shape of it: KWin creates the output, leaves it
disabled, and workspace()->findOutput() returns null — reported identically to
a backend that cannot create one at all.
enricobuehler
b551f7dae8