The Tab Groups' tab twisty icon does not show up in Pale Moon 28, I have been unable to determine why.
Workarounds:
The keystroke [Ctrl][Alt]-[+] will expand the current selected tab group
** (or all tab groups if none are selected or the current tab group is already expanded)
The keystroke [Ctrl][Alt]-[-] will collapse the current selected tab group
** (or all tab groups if none are selected or the current tab group is already collapsed)
Right click on a tab group tab, under the "Tab Stack" submenu select "Expand Stack" or "Collapse" stack as needed.
The Tab Groups' tab twisty icon does not show up in Pale Moon 28, I have been unable to determine why.
Workarounds: