You can already enable the menubar from the rightclick menu in the toolbar, no need to go into full toolbar customization for that, simplifies first section to 1 item… 
Compact UI can be enabled but I get the info it is not supported and cannot see any change…?
The crash should be easy to fix @KENZ - it’s just a missing BLooper::Lock() call:
thread 2118: w>Customize Nightly — Nightly
state: Call (looper must be locked before proceeding
)
Frame IP Function Name
-----------------------------------------------
00000000 0x15d3eb403f7 _kern_debugger + 0x7
Disassembly:
_kern_debugger:
0x0000015d3eb403f0: 48c7c0eb000000 mov $0xeb, %rax
0x0000015d3eb403f7: 0f05 syscall <--
0x7fcc1c528210 0x681cbea9f2 BLooper::AssertLocked() const + 0x22
0x7fcc1c528230 0x681cbeae2c BLooper::Unlock() + 0xc
0x7fcc1c528270 0x6338ce2180 WaylandView::Draw(BRect) + 0x60
0x7fcc1c5282a0 0x681cca19bf BView::_Draw(BRect) + 0x9f
0x7fcc1c5284d0 0x681ccaf287 BWindow::DispatchMessage(BMessage*, BHandler*) + 0xcb7
0x7fcc1c528560 0x681ccaa883 BWindow::task_looper() + 0x1d3
0x7fcc1c528580 0x681cbeb75b BLooper::_task0_(void*) + 0x1b