I’m working on an app that is delivered for both platform UWP and WinUI 3. In UWP, when I misspell or provide an invalid FontFamily, it seems to fall back to Segoe UI Variable. However, in WinUI 3, the fallback appears to be different and the Segoe UI Variable has different sizes in comparison to UWP.
In our UWP app, we explicitly set all TextBlock elements to use Segoe UI Variable, but when migrating to WinUI 3, we noticed that the "text box" size and layout appeared different. Interestingly, when we intentionally provide an invalid font family name in WinUI 3, the result visually matches what we had in UWP, suggesting that a different fallback font is being used compared to Segoe UI or Segoe UI Variable.
We tested various Segoe fonts (Segoe UI, Segoe UI Variable, Segoe UI Historic, etc.) but none of them visually matched the fallback font rendered when the FontFamily is invalid in WinUI 3.
Could you please clarify which font is used by default in WinUI 3 when an invalid or non-existent FontFamily is specified?
WinUI
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UWP
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WinUI
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UWP
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Thank you in advance!