1694295 - What is an SVG's min-content contribution without a specified width

Status: NEW

(Core :: SVG, defect)

Description

[Ting-Yu Lin [:TYLin] (PDT, UTC-7)]

Attachment: svg-min-content-contribution.html

After fixing bug 1674302, https://webcompat.com/issues/55006 can reduce to the following question: what is an SVG's min-content contribution without a specified width?

See the testcase attached. We get 0px where Google Chrome get 150px.

Comment 1

[Robert Longson [:longsonr]]

That svg element is a replaced element so it should follow the rules for replaced elements. 150px is the fallback size for replaced elements when their width cannot be determined as in this case.

https://drafts.csswg.org/css-sizing-3/#auto-box-sizes says

min-content
    Use the min-content size in the relevant axis; for a box’s block size, unless otherwise specified, this is equivalent to its automatic size.

That seems at first glance to point to 0 as being the correct answer per https://drafts.csswg.org/css-images-3/#natural-dimensions since the svg in this case has no natural dimensions, not even a preferred aspect ratio as it's lacking a viewBox.

Not sure the specs are very clear here though.