Feature Request: lowercase all hex values (and possibly other attribute values?)

[albell]

Reasons:

• Gzipping is more efficient with consistent, repeated character case.
• There are some browser bugs in which uppercase attribute values throw errors.
• All lowercase is a strong convention for most markup and css.
• It would make find-and-replace operations consistent.

[GreLI]

Well, all these reasons are debatable, but as an option it may be.

[albell]

Well, there's no debate about gzipping. Compressors get more string matches when case is consistent. Some data:

http://www.websiteoptimization.com/speed/tweak/lowercase/

And in terms of the overall web ecosystem the bias seems to be strongly towards lower case. If you disagree or have conflicting data on this I'd love to see it. I can't find a single CSS styleguide on the web that recommends upper case anything.

[GreLI]

Sure, but most values are in lowercase already. Will it give any significant profit? 7-zip or zopfli can give much more. That's why I say it debatable.

[SethFalco]

Thanks for reporting the issue.

The specific scenario presented here regarding hex colors has been addressed in #1692 and is already in the latest release.

I have not acted on the proposed browser bug for spreadMethod for now, as I see nothing suggesting PAD in uppercase is an acceptable value, and converting an invalid value to a valid one would be a breaking/visible change in the SVG.

If you have any concrete examples of safe case conversions we can do, feel free to open issues, and we can look into them. As the issue as it is written now is fairly open-ended, I'll take it more as a consideration maintainers must have in future rather than something to act on immediately.