Set exact boolean value to color property

This is a regression since 48e9e5f4
3 jobs for fix-bool-on-color in 4 minutes and 37 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #1751300
mingw-build

00:03:44

passed #1751298
shared-build

00:04:37

passed #1751299
static-build

00:03:38