Font embedding or: better typeface substitution on MuseScore.com, using a font server or listing fonts available at MuseScore.com
I use the Cambria and Calibri typefaces on my scores, for titles and lyrics respectively, and also add manual system breaks. They look very nice on my computer (Windows 10) or on any PDF I export.
However, uploading the scores to MuseScore.com makes the typeface Cambria to be substituted by Caladea and Calibri by DejaVu Sans, breaking the layout to the point some systems have only one measure. It is very ugly when it happens.
Fonts such as Cambria and Calibri can be embedded on documents to the point they are allowed to be editable and not just printable: See https://docs.microsoft.com/en-us/windows/win32/gdi/embedded-fonts and the font properties, they have the "editable embedding" allowed; also see https://docs.microsoft.com/en-us/typography/fonts/font-faq, principally https://docs.microsoft.com/en-us/typography/fonts/font-faq#document-emb…, https://docs.microsoft.com/en-us/typography/font-list/cambria#licensing… and finally https://docs.microsoft.com/en-us/typography/font-list/calibri#licensing….
MuseScore should allow us to embed fonts which have the proper bits for embedding, so that scores uploaded to MuseScore.com would appear exactly as they were formatted.
In the meanwhile, or in the case you think font embedding is not in the project's scope, MuseScore.com should substitute those fonts for metrically equivalents. There is a list of metrically equivalent fonts at https://wiki.archlinux.org/index.php/Metric-compatible_fonts, where you can see the best match for Calibri is not DejaVu Sans, but Carlito (an open source typeface). Best of all, they are all free and open source or, in the case of the Core Fonts for The Web, licensed to be used commercially (the Core Web Fonts) without paying licensing fees.
Another solution is to use free and open source font servers such as Google Fonts and FontLibrary.org, so when we upload a score with one of those fonts, they will be rendered exactly as they were intended.
But the minimal thing that is super easy to do is to make a list of available fonts at MuseScore.com, so we can try typefaces that will not break our scores' designs.