Bug 487681

This behaviour also affects some other applications such as Kdenlive where clicking and holding the video timeline selects window move in the same way. This makes editing almost impossible.

This is a Breeze setting. You're welcome to turn it off in System Settings > Colors & Themes > Application Style > Click the pencil icon on "Breeze" > Windows' drag mode> Set it to a different value from what it's currently set to.

We can consider changing the default value, as this does seem to accumulate a lot of complaints, particularly from Kdenlive users.

I bet if we changed this to only allow dragging from the Tools Area (Titlebar, menubar, and toolbar), nobody would complain. Let's consider it.

(In reply to Nate Graham from comment #2)
> This is a Breeze setting. You're welcome to turn it off in System Settings >
> Colors & Themes > Application Style > Click the pencil icon on "Breeze" >
> Windows' drag mode> Set it to a different value from what it's currently set
> to.
> 
> We can consider changing the default value, as this does seem to accumulate
> a lot of complaints, particularly from Kdenlive users.
> 
> I bet if we changed this to only allow dragging from the Tools Area
> (Titlebar, menubar, and toolbar), nobody would complain. Let's consider it.

Having a play with the settings in Kdenlive it is possible to select Breeze as window style which now has "windows drag mode" set for header only. Most other windows only have minor irritations like the scroll bar becoming the drag item for the window. 

I have used QTcurve style for some time as it has many config options as my default. It still works well in Plasma 6 though the configure panel no longer appears. Editing the config file allows adjustments though a fresh config may be hard work. Maybe I can get the developer to fix this and ensure Plasma 6 compatability. It probably does not have a setting for this at the moment.

Alternatively a global setting for drag behaviour would make sense for all styles?

A possibly relevant merge request was started @ https://invent.kde.org/plasma/breeze/-/merge_requests/468

Git commit cd34b95d74bc5b39e5004f08dd5519fbdfd7fcbc by Nate Graham.
Committed on 21/06/2024 at 17:50.
Pushed by ngraham into branch 'master'.

Use "drag from Tools Area" by default, not entire window

Currently Breeze allows you to drag the window from all empty parts of
window backgrounds that are not scrollable content views. This has
caused some problems over time, especially with control-dense apps that
have draggable controls on non-scrollable areas.

Ever since we introduced the "Tools Area" style that visually unifies
the titlebar, menubar, and toolbar, there's a natural visually distinct
area to grab if you want to drag the window around.

So let's change this setting so that you can only grab on a part of the
Tools Area to drag the window. This preserves a large drag area but
eliminates usability problems associated with making other areas
draggable.
FIXED-IN: 6.2

M  +1    -1    kstyle/breeze.kcfg

https://invent.kde.org/plasma/breeze/-/commit/cd34b95d74bc5b39e5004f08dd5519fbdfd7fcbc

(In reply to Nate Graham from comment #2)
> I bet if we changed this to only allow dragging from the Tools Area
> (Titlebar, menubar, and toolbar), nobody would complain. Let's consider it.

I can positively guarantee that somebody (me) *will* complain if this new "default" quietly changes behaviour on existing installations / user configurations.

They'll just have to be irked, unfortunately. We don't have an easy way to prevent defaults changes from affecting everyone right now.