DO11: Conflict between style setting and button code

I know the following button code contains some nonsense but I'm sure you'll want to know about serious effects like a frozen viewerpane.
What I wanted to do was to create a button that toggles between a single display style with viewpane and a dual display style using @ifset. When toggling back to the dual display the last paths should be remembered. Since Set Dual=remember didn't work (shouldn't it?) I tried Set Dual=On,remember which caused serious problems. Here's the button code with which you should be able to reproduce the problem:

@ifset:viewpane=toggle Set DUAL=On,Remember Prefs STYLE=Dual @ifset:else Prefs STYLE=SingleThumbs Show THUMBNAILSIZE 247
The dual path opened new tabs (no tabs should be present):


Closing the active tab resulted in this:


As you can see the display border is black and above the column header. Close the empty tab at the left display and you're back to single display.
The reason why this happens is because the command Set Dual=On was already set in the style and doubled by the button code. I had to clone my Dual style with disabled dual display option to make it work.
To further examine this problem I added a line Set VIEWPANE=On as 6th line to the above code. As you can see in screenshot 4 the result is a double viewpane. Closing one of them results in a frozen pane that is unresposible and always on top of the display:


My suggestion to avoid this sort of problems is to ignore style settings when they're doubled by a button code. Not every user is aware of all the settings in his styles. This way calling a dual style with a second line like Set DUAL=On,remember could work. Apart from this the command Set DUAL=remember should work on its own when calling a dual style.

EDIT: I uploaded the wrong screenshot with the frozen doubled viewpane. Screenshot 3 shows what happens after closing one of them. Here's the one with double viewpane:


"Set DUAL=remember" is like "Set DUAL" on its own, and won't do anything as it isn't telling Opus what to set it to. You have to add an argument like On, Off or Toggle to make it mean something. (See the manual.)

The other things seem like bugs, but I cannot reproduce them in Opus 11 Beta. Which version are you seeing them in?

The bug with the tabs is not always reproducable for me (but at ~97%). Sometimes no new tab will be opened by the button when toggling back to the dual/details style. Everytime I'm getting a new tab (quickly clicking the button twice seems to force this) it's the same behaviour with DO11 Beta3: A single click to (one of) the inactive new tab(s) closes the tab and the display border gets black with no tab bar and no column header at the right display while the left diplay stays normal. As you can see in the screenshot he black toolbar shows up below the display border on top of the colum header:

Click inactive tab



Result


The doubled frozen Viewpane issue didn't always appear with Beta2 but at ~70%. With Beta 3 I could only once force it to happen by quickly clicking the button several times. The viewpane wasn't doubled but frozen this time. Can't reproduce this anymore now.

EDIT: The two styles are also toggling dual/single location toolbars. Maybe that's important to reproduce the issue.

Another setting that may be important: Tabs are configured to not showing the tab bar at all if no tabs are opened.