ShadowFox/css/userContent-files/webextension-tweaks/onetab.css

@-moz-document url-prefix("moz-extension://extension@one-tab.com") {
  .clickable span {
    color: var(--in-content-link-color)!important
  }
  .clickable div {
    box-shadow: none!important;
    background-color: var(--in-content-box-background)!important
  }
}