Setting the weight level of a vertex group is very un-intuitive

Not sure about this, if it was staying on the vertexgroup which was selected when executing the operator [aka: if the confirmed bug would be resolved], what would be so "un-intuitive"?

The (unwanted) changing of the vertexgroup after execution is only happening if the user actually changed the vertexgroup directly before the execution
This is the same issue as T69760: Undo/Adjust Last Operation: vertex and weightpaint operators/strokes undo more then they should (change back any setting changed prior to execution), will merge these reports...

In T73302#855490, @Philipp Oeser (lichtwerk) wrote:

Setting the weight level of a vertex group is very un-intuitive

Not sure about this, if it was staying on the vertexgroup which was selected when executing the operator [aka: if the confirmed bug would be resolved], what would be so "un-intuitive"?

@Todd Gillissie (Gillissie) : if there is another issue that is not covered by T69760, please report this seperately, thx

It's unintuitive because it's very unclear how the tool panel works.
Here's how it currently works (if it worked properly)...

1. Select a vertex group.
2. Choose the "Levels" menu item.
3. Set the desired values in the tool panel.
4. There is no confirmation button, or any other clear way to dismiss the tool panel after you've set the values you want.
5. Choose another vertex group.
6. Set the values in the tool panel. What? It affects the previously selected vertex group instead?

6a. To make it work, you have to again select the "Levels" menu item after selecting the next vertex group, although there is NO DIFFERENCE in how it appears on the screen. No indication of what vertex group the panel is affecting.

To make it more intuitive, the tool panel would have a way to confirm/dismiss the input values for the selected vertex group, OR the panel would automatically disappear when selecting a different vertex group, forcing you to choose the Levels menu option again, making it clear that the new panel is for the newly selected vertex group.

Please re-open this ticket as originally reported, with my additional explanation of the unintuitive nature of the tool.

Choose another vertex group.
Set the values in the tool panel. What? It affects the previously selected vertex group instead?

This is the bug already reported in T69760 (you execute the operator, and if you changed the vertexgroup right before that it will undo that change as well resulting in this weird behavior, definitely a bug!)

There is no confirmation button, or any other clear way to dismiss the tool panel after you've set the values you want.
To make it work, you have to again select the "Levels" menu item after selecting the next vertex group, although there is NO DIFFERENCE in how it appears on the screen. No indication of what vertex group the panel is affecting.
To make it more intuitive, the tool panel would have a way to confirm/dismiss the input values for the selected vertex group, OR the panel would automatically disappear when selecting a different vertex group, forcing you to choose the Levels menu option again, making it clear that the new panel is for the newly selected vertex group.

This is all behaving as designed atm. The Adjust Last Operation panel stays as long as you dont execute another operator. Selecting a vertexgroup is not an operator (in contrast to e.g. selecting a vertex - in which case the panel would close), so this panel stays open. In the particular case of this report, this is a bit unintuitive and maybe can be improved upon in the future, but it is not considered a bug atm...
When the real bug will be fixed, this will also be a bit less of an issue.
A "confirm" type of button would not really work out nicely since you wont see your changes in realtime then...

The panel could still operate exactly as it does, with realtime feedback, but the ability to dismiss the panel when finished would be the expected design. I've never seen any other software behave the way that tool panel does, where it just sits there forever after you're done, potentially allowing for further accidental changes. As suggested, selecting a different vertex group should make it go away too, especially if selecting a vertex makes it go away already. Consistency is good.

In T73302#856094, @Todd Gillissie (Gillissie) wrote:

The panel could still operate exactly as it does, with realtime feedback, but the ability to dismiss the panel when finished would be the expected design. I've never seen any other software behave the way that tool panel does, where it just sits there forever after you're done, potentially allowing for further accidental changes. As suggested, selecting a different vertex group should make it go away too, especially if selecting a vertex makes it go away already. Consistency is good.

Probably agree here (at least for some situations), but still not a bug...
Please use other channels for user feedback and feature requests: https://wiki.blender.org/wiki/Communication/Contact#User_Feedback_and_Requests
For more information on why this isn't considered a bug, visit: https://wiki.blender.org/wiki/Reference/Not_a_bug

Ok, I can post in the requests. I always get the feeling that they aren't looked at though.
Question on this topic... what is the expected behavior if the tool panel is showing for a vertex group operation, then you select a different vertex group and make changes to the still-showing tool panel?

The bug mentioned in this thread is still not fixed in blender 2.91.0 as well. Even there are few more issues related with "Levels" which we're facing.
Can any moderator please guide me to the right files where I can edit the "Levels" in blender source and fix it?
In our case we've been encouraging our art team to switch to Blender and issues like these are quite annoying.