so it is not possible to use right click on buttons (as the panel is gone already) or to open a linked toolbar from triangle in bottom right corner of an icon.
Rhino 9.0.26202.12303, 2026-07-21
Hi Yury,
This one is already on the list — RH-97126 Popup menu: vanishes when mousing out. The popup should stay up after releasing the wheel so you can still click, right-click or open the cascade from the triangle. It came out of the recent fix for RH-97067 (release-to-execute on the popup), more discussion here: Popup toolbar mouse button release execution broken (again)
i’ve added your thread to the issue. Thanks for reporting
Hello, I am still having this issue (pop up appearing and disappearing immediately when using the Middle Mouse Button) using a trackpad in Rhino 9 Beta (9.0.26216.12303, 2026-08-04). Of note: the MMB function (on my trackpad at least) is a “triple-tap”. Normally this does not include a “press and hold it down” function, it’s just a quick light tap with 3 fingers simultaneously.
Some diagnostics:
- The trackpad still works great to bring up the popup window in Rhino 7 and 8, no issues.
- I’ve tried different trackpads, they all work in Rhino 7 and 8, and all don’t work in Rhino 9 Beta.
- In R9B, with the trackpad, pop-up disappears immediately 80 or 90% of the time. Once in a while you get lucky and it stays up there.
- Varying the speed, pressure, location, etc. of the triple-tap doesn’t matter.
- Tried “press and hold the triple tap down and then slowly release” and it doesn’t do anything.
- The button in the very center of the popup window, which the cursor is hovering over automatically, seems also to get automatically pressed. In my case, this is the Polyline button, so whenever I bring up the popup window, I’m effectively clicking Polyline.
- I tried a workaround where I created a custom “empty” (no action) button in the middle of my popup window, hoping that button would get clicked, nothing would happen, and the popup would stay open. Did not work, popup window opens and closes immediately as usual.
- I tried the Advanced >> UseNewToolBarPopUps=True solution, but it creates more problems than it solves. Popup stays open but it’s too large, in the wrong array, and automatically fans out flyaway menus wherever the cursor moves, making it effectively unusable.
So, I’m still stuck, can’t quite use Rhino 9 Beta yet… 
@RhinoFan01 yes, the issue was reopened shortly after it was marked fixed.
I have it on good authority this is currently being worked on. Stay tuned for a fix
I confirm that Today’s (Dujour) build resolved the issue, Thank you everyone.