Vieb theme: Similar to vertical tabs, but make the pinned tabs occupy a full line and give them a right border to show they are pinned.

verticaltabs-pinned-fullwidth-rightborder.css

#tabs {overflow-x: hidden;overflow-y: auto;position: absolute;left: 0;width: 15vw;max-height: calc(100vh - 2em);top: 2em;flex-wrap: wrap;}
#tabs > span {min-height: 1.9em;max-height: 1.9em;min-width: 14vw !important;width: 15vw;}
#page-container {height: calc(100vh - 2em);position: absolute;top: 2em;left: 15vw;width: 85vw;}
#app.fullscreen #page-container {height: 100vh;width: 100vw;top: 0;left: 0;}
#app.tabshidden #page-container {width: 100vw;left: 0;}
#app.navigationhidden #page-container {height: 100vh;top: 0;}
#app.navigationhidden #tabs {top: 0;max-height: 100vh;}
#tabs::-webkit-scrollbar {width: .2em;height: auto;}

#tabs .pinned {min-width: 14vw !important;max-width: 15vw;width: 14vw;border-right: solid 2px red;}