Ui ifxes (#5890)

* PLT-5975 - Back arrow in flag list cutting off

* PLT-6049 - Fixing pin icon color, and hover state

* PLT-5989 - Channel member and pin icon issue

* PLT-6067 - Pinned icon misaligned in firefox

* PLT-5885 - Adjusting icon spacing in modal

webapp/sass/layout/_headers.scss

@@ -44,6 +44,7 @@
             font-weight: normal !important;
 
             &.header-list__right {
+                white-space: nowrap;
                 padding-right: 4px;
             }
         }