Just testing this, looks good - with a few issues.

In my dark theme Joplin, this shows up as white text on a white background. I've tried to adjust this using the devtools + userchrome.css but it doesn't seem to work:

.resource-name-cell {
    font-family: helvetica;
    color: rgb(248, 248, 242);
    padding: 3px;
}

.referencing-notes-cell {
    font-family: helvetica;
    color: rgb(248, 248, 242);
    padding: 3px;
}

#search-results {
    background: rgb(40, 42, 54);
}

Any chance of adding something to the user options, or some help with the CSS here?