Since twig/twig 3.12: Twig Filter "spaceless" is deprecated.

drunken monkey → made their first commit to this issue’s fork.

Thanks for reporting, makes sense to get ahead of this and fix it right away. Seems easy enough, after a bit of digging (since, helpfully, no-one just tells you how this can be resolved).
This should do it, please test/review!

Merged. Thanks again!

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