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Do we need to resolve custom properties?

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#972 1 comment 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
css

Research direction

No file or test is named. Start by reviewing how the build system handles the variables option and the browser support targets referenced in pull request #970; compare resolving variables at build time with emitting :root custom properties, including first-paint and compressed-size effects. Done means reaching a documented decision on whether to change the build behavior.

Written by the indexing model from the issue text.

Description

2 estimate-2 icebox jira-sync-complete p2

With https://github.com/mapbox/assembly/pull/970 - our browser support targets all support css custom properties. Should we revise our build system to convert the variables option to a set of :root CSS properties? Would save us from needing to resolve every variable in our CSS at build time.

Are there costs to doing this? Likely compressed file size would not be impacted but could time to first paint take a hit? Here's an article on CSS variable performance, but it exclusively discusses the performance of changing variables at runtime: https://lisilinhart.info/posts/css-variables-performance/ and after some quick looking, couldn't find any existing documentation of the performance cost of using variables.

Dominant language
CSS
Stars
138
Forks
26
Avg merge
20m
Merged PRs (30d)
3

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