w3c / w3c/css-validator

image-set property is reported as an error... incorrectly

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#388 2 comments 1 reaction 0 assignees View on GitHub

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Java
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Description

Hello,

The image-set property is not recognized by w3c Jigsaw validator. Here is an example from MDN image-set page:

.box {
  background-image: -webkit-image-set(
    url("small-balloons.jpg") 1x,
    url("large-balloons.jpg") 2x);
  background-image: image-set(
    url("small-balloons.jpg") 1x,
    url("large-balloons.jpg") 2x);
}

The validator seems to recognize only the -webkit version.

Source : https://developer.mozilla.org/en-US/docs/Web/CSS/image/image-set

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the MDN image-set example from the issue in the W3C CSS Validator. Trace how the validator recognizes the prefixed and unprefixed image-set forms. Done means the unprefixed property is accepted without an error while the existing example remains valid.

Written by the indexing model from the issue text.

Assessment

Tech stack
css
Domain
tooling, web-dev
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
45/100

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