Steps to replicate the issue (include links if applicable):
SVG files which use WMF specific language codes (such as ISO 639 codes) do not work because they do not match the BCP47 codes used by librsvg, WMF's thumbnailer for SVG's. Split from T337139
What happens?:
SVGs with these WMF language codes show no text.
What should have happened instead?:
This could be fixed in two ways:
- Post to tech news to prompt users to change from WMF specific codes to BCP47
- Make a WMF langcodes to BCP47 converter, maybe reuse the BCP47 parser function.
The common practice with Thumbor and its dependencies has been to follow standards, which the WMF codes do not. It is more likely that the first point will be done, but it is not my decision to make.
Software version (on Special:Version page; skip for WMF-hosted wikis like Wikipedia): WMF
Other information (browser name/version, screenshots, etc.):