Gradients in background styles are no longer ignored and are properly normalized.

[Mati365]

🚀 Summary

Gradients in background styles are no longer ignored and are properly normalized.

It's now possible to preserve more complex background properties:

background: linear-gradient(90deg, rgba(161, 29, 125, 0.55) 0%, rgba(24, 33, 104, 0.75) 100%), linear-gradient(180deg, rgba(255, 200, 0, 0.4) 0%, rgba(255, 100, 0, 0.6) 100%) center #f00 repeat-y fixed

was previously downcasted to:

background-color:#f00;

it's now downcasted to:

background: linear-gradient(90deg, rgba(161, 29, 125, 0.55) 0%, rgba(24, 33, 104, 0.75) 100%), linear-gradient(180deg, rgba(255, 200, 0, 0.4) 0%, rgba(255, 100, 0, 0.6) 100%) center repeat-y fixed #f00;

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📌 Related issues

• Closes Collision between linear gradient backgrounds and TableProperties #19787

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[niegowski]

Partial review.

I asked Marta for CR

[mmotyczynska]

LGTM 👍
After going through the code and tests, I mostly focused on trying different scenarios. It was already reviewed a few times, and now everything looks solid 👍