Created attachment 134346 [details]
When svg is included inline with text in an html document with the width defined and a viewbox, it negotiates a 100% height. Other browsers set the height to preserve the given width and aspect ratio from the viewbox, as one would hope for.
As noted in the other bug report 82487, intrinsic sizing for inline SVG is just not implemented yet. Fortunately the framework for that is finished, it's just a matter of actually finishing it :-)
Just a note for future visitors, I had luck setting max-height: 100% on the inline svg element as a workaround.
Fixed as well.