Popup toolbar mouse button release execution broken (again)

This has been a sporadically recurring problem during WIP/Beta developement since… I can’t remember when, at least back to Rhino 7 or maybe earlier.

When one has the popup toolbar on-screen - after having called it up using a MMB press for example - with the MMB still held down, hovering over a button and releasing it should execute the button command.

In the current Beta, I note it is broken again. One has to release the MMB and then LMB click the desired popup toolbar button to execute the command.

This has periodically happened in various development stages from Rhino 6/7 or so on, followed by reports from me and other people who heavily use this functionality, and subsequently fixed again. It currently works correctly in Rhino 5/6/7/8/. I assume that this problem is a by-product of the current toolbar UI revamp and probably just an oversight. @CallumSykes

Related to this workflow is using a left-click/hold to flyout a linked toolbar, and with the LMB still held down, hovering over the desired button and then releasing it to execute the command. This is actually working correctly in the current Beta. The popup toolbar needs to work in the same way with a MMB click/hold.

Hi Mitch,

yep - same as RH-78837 from the 8.5 fix, knocked out again by the 9 toolbar rework while the LMB flyout path still holds it. logged as RH-97067 and referenced the original as a regression. @CallumSykes

can you drop the exact build you’re on (Help > About)?

Latest public I think - (9.0.26195.12303, 2026-07-14)

Thanks for reporting!

RH-97067 is fixed in Rhino BETA

I"m kinda confused on whats going on with the MMB popup after the latest release. I think there is a missing delay?

I MMB click (down and up quickly) and where my mouse is, that command fires off. I just want to click and make the toolbar visible.

Sorry for this

RH-97126 Popup menu: vanishes when mousing out

@CallumSykes This is a huge problem for me. Where can I download the previous Beta?

Would the above not effectively halve the number of commands that one could call from the popup, because there’s no left click/right click option?

Personally, that’s not the behaviour I’d like to see. The old Rhino setup works very well. It’s one of my favourite Rhino UI features: MMB/scroll wheel single click and release to make the popup toolbar appear. The popup then sits there and waits for one to left or right click on the desired button, or select a further fly out.

Hey @MattE, both are possible. There’s a 750ms timeout for this in 8. If you hold for >= 750ms then the pop-up dissappears and runs whatever your mouse is held over. I misunderstood this when applying some fixes in 9. It’ll be solved in next weeks build so it’ll work like you both expect.

Also @Helvetosaur I’ve added the delay to the settings so you can tweak it if you so wish.

Correction it is 400ms. Next build will have the fix in, as well as allowing for the Cascade As Menu for the PopUp.

Hi.

Open the Popup panel. Click the icon using the middle mouse button—it doesn’t work. In Rhino 8, it works. Instead, it only responds to the left mouse button.

I also noticed that it doesn’t work with the other toolbars either.

Actually it also responds to the right mouse button if there is a RMB command under the button - like other tools. I have never used a middle click to run a tool, wasn’t even aware that this worked in V8 until you mentioned it. Does not seem to work on any toolbar button in the WIP.

You are correct, I noticed this whilst working on things and wondered if anyone actually used the middle button to click left.

YT : RH-97326 MMB should click icon as if a left click

RH-97326 is fixed in Rhino BETA