This extension overrides bracket highlighting behaviour with something resembling VSCode's indent guide highlighting.
This may slightly increase the CPU load for cursor navigation in very large files.
If your theme implements rainbow brackets, you can do that too, like so:
/* curly brackets */
#main .ace-tm .ace_curly.ace_paren.ace_depth1 {
color: #C6FF79;
}
/* bracket match rectangles and lines */
#main .ace-tm .ace_marker-layer .ace_bracket.ace_depth1,
#main .ace-tm .ace_marker-layer .ace_bracket_line.ace_depth1 {
border-color: #C6FF79;
}