One layer merges
Rather than have a merge of a single visible layer result in an error message,
would it be preferable to have the operation apply the Opacity setting to the
layer?
ADVANTAGES:
* Eliminates an error message pop-up.
* More intuitive. Merging down first applies the Opacity and then combines the
layers. This method would retain the first step.
* Eliminate the need to create a new transparent layer and merge that to apply
the opacity. (At least, that's how I accomplish this.)
* _Shouldn't_ affect plugins. I wouldn't think a plugin programmer would depend
upon the GIMP core to control error interfaces with the user.
DISADVANTAGES:
* Eliminates a "stupidity check" for the user. (I prefer to assume a user knows
what he is doing.)
* _Might_ impact other parts of the GIMP. Perhaps this would have an affect on
things such as exporting; which is why I am asking.
I would be willing to pursue implementing this change if it is deemed desirable.
