File module's FilemimeFormatter icon display renders empty image

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The patch in #2907414-31: File module's FilemimeFormatter icon display renders empty image → produces 4 additional files

core/b/core/modules/file/templates/file-mime-icon.html.twig
core/b/core/themes/classy/templates/field/file-mime-icon.html.twig
core/b/core/themes/stable/templates/field/file-mime-icon.html.twig
core/b/core/themes/stable9/templates/field/file-mime-icon.html.twig

that do not differ from the ones at their correct location.

Attached patch should fix it.

This patch should be added to the new separate modules classy, stable and stable9.
I'll open issues there, too.

Sorry - the patch itself is correct. It's just composer-patches that messes things up in case of newly created files.
Because it tries all values of patch's -p0 till -p4, it creates new files everywhere. Currently investigating how to prevent that.

"patchLevel": {
            "drupal/core": "-p2"
        },

that's how you prevent that.

Yeah, thanks, found out in the meantime.

This is https://github.com/cweagans/composer-patches/issues/514

It has the potential to considerably mess up an installation or even create files in locations where they get read/parsed/interpreted.
Using patches is safer than using git repos for fixing up stuff, but this is a pretty hefty disadvantage. I don't remember seeing a warning for this in any doc regarding patching (but I may be wrong).

Patch for 11.x.
Could not find this file core/tests/Drupal/KernelTests/Core/Theme/ConfirmClassyCopiesTest.php