Colors do not reset in custom highlighters

[jultty]

First of all, thank you for your work on this plugin. I am trying to create a custom highlighter, and it works perfectly. The issue is that the next commands also get highlighted at the same positions the prior command was highlighted at.

I created a minimal example to reproduce this, which I tried in a clean containerized environment:

.zshrc:

ZSH_HIGHLIGHT_HIGHLIGHTERS+=(main brackets demo)
source zsh-syntax-highlighting-master/zsh-syntax-highlighting.zsh

zsh-syntax-highlighting-master/highlighters/demo/demo-highlighter.zsh:

: ${ZSH_HIGHLIGHT_STYLES[demo:red]:=fg=red,bold}

function _zsh_highlight_highlighter_demo_predicate {
    [[ $BUFFER[1,4] == echo ]]
}

function _zsh_highlight_highlighter_demo_paint {
    _zsh_highlight_add_highlight 4 10 demo:red
}

An example output can be seen in this image.

Unless I understood the docs incorrectly, the paint should apply only to the echo calls. I tried similar simplistic conditions, such as the length of $BUFFER being above a given number, with similar results.

If there's something I'm missing, I'd appreciate any pointers. Also, I could not get the main highlighter to apply unless explicitly added to ZSH_HIGHLIGHT_HIGHLIGHTERS, which I suppose is unrelated but also contrary to documentation.