The original kaios-native-ui was using a fancy mask-image property,
which was unfortunately a bit *too* fancy for KaiOS to handle.
Instead, we've fallen back to good ol' conditions and a number of
new SVGs for the selected version of the checkbox. The drawback is,
of course, that selected checkboxes will perforce be white (which
can be easily overridden to black if so desired, but not so easily
to any other colour: Inkscape is your friend though).
Badri Sunderarajan
aa0f1c5641
