Does anyone know if anything changed with the new tab settings?

I used to have this custom userContent.css to add more columns to topSites described below, but it is no longer working after I updated :/

https://support.mozilla.org/en-US/questions/1430289

folder named “chrome” and file named “userContent.css” are still there

@-moz-document url(about:home), url(about:newtab) {
  @media (min-width: 1800px) {
    .ds-outer-wrapper-breakpoint-override main {
      width: 1700px !important;
    }
  }
}

edit: If anyone has any suggestions to add more columns to topSites, let me know edit2: solved