Comment by aenopix

Ublock Origin in Firefox:

``` ! Display 6 per row youtube.com##ytd-rich-grid-row, #contents.ytd-rich-grid-row:style(display:contents !important;) youtube.com##ytd-rich-grid-renderer, html:style(--ytd-rich-grid-items-per-row: 6 !important;) youtube.com##ytd-rich-grid-renderer, html:style(--ytd-rich-grid-posts-per-row: 6 !important;)

! Block on profiles "/videos" youtube.com##ytd-rich-grid-row:matches-path(/.\/videos/):style(display: none !important) youtube.com##ytd-rich-grid-renderer:matches-path(/.\/videos/):style(--ytd-rich-grid-items-per-row: 4 !important) ```