Twig\Error\SyntaxError: Unknown "spaceless" tag.

Drupal 10 uses Twig 3.x, where the {% spaceless %} tag was completely removed in favour of the {% apply spaceless %} filter. The codebase of barrio bootstrap 5 is also using {% apply spaceless %} filter in the latest version, so could you explain the steps to reproduce the issue?

Rajan Kumar@2026 → changed the visibility of the branch 3399149-twigerrorsyntaxerror-unknown-spaceless to hidden.

Hi@trickfun,
i'm tested this twig files
dropbutton-wrapper.html.twig
link-formatter-link-separate.html.twig
select.html.twig
toolbar.html.twig
but all ready used
{% apply spaceless %}

apaderno → changed the visibility of the branch 3399149-twigerrorsyntaxerror-unknown-spaceless to active.

I confirm #3 and #4. (5paceless has been fixed in 5.5.7 and 5.1.6).