I found the solution after some searching.
You need to add a <meta>
tag in your <head>
containing name="theme-color"
, with your hexadecimal code as the content value. For example:
<meta name="theme-color" content="#999999" />
If the Android device has native dark-mode
enabled, then this meta
tag is ignored.
Chrome for Android does not use the color on devices with native
dark-mode
enabled.
Source: theme-color Meta Tag