The active page highlight color doesn't work when using the color by default by not declaring the palette configuration. You are required to declare the palette colors for active page to work.
The active page highlight should work when not explicitly declaring the palette. It should use the colors by default.

The active page highlight doesn't work when not explicitly declaring the palette.

mkdocs serve and see the active link not being highlighted Just remove the palette configuration from the mkdocs.yml
That is indeed a regression. Thanks for reporting, will provide a fix.
Fixed in 94acf18d5dfe72969304a0c37ddd1866aa55ce02, another regression, thanks for reporting. Really need to set up visual regression testing.
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Fixed in 94acf18d5dfe72969304a0c37ddd1866aa55ce02, another regression, thanks for reporting. Really need to set up visual regression testing.