SVG files embedded into CSS should be passed through svgo [1] or some similar SVG minification software first, to reduce size. (Ideally the same should happen for non-embedded files, but that seems more complicated.) Per [2], size reduction can be as much as 90%.
[1] https://github.com/svg/svgo
[2] https://gerrit.wikimedia.org/r/#/c/103894/
Version: 1.23.0
Severity: enhancement
| Status | Subtype | Assigned | Task | ||
|---|---|---|---|---|---|
| Duplicate | None | T59777 CSSMin::encodeImageAsDataURI() should be smarter about SVG images (tracking) | |||
| Duplicate | None | T65491 Embedded SVG files should be optimized in ResourceLoader/CSSMin |
SVGO is too buggy to use transparently in its current version (see the long history of the patch you linked and https://gerrit.wikimedia.org/r/#/c/106506/ ).
Related: bug 59744.
What about using SVGO plus a post-processing script to fix the bugs? Right now, a lot of teams are minifying their SVGs locally, which not only makes them harder to edit later, but breaks the SVGs in many cases.
I don't think it's possible to write a script to recover information incorrectly deleted by svgo, we should rather fix its bugs.