Improvement for message if a class uses @extends accidentally a second time

[Jugibur]

Hi,
I'm in the process of changing a third-party WordPress theme that still uses "@import" to "@use".
Thereby a class was extended via @extend a second time in two different files.
Following a simplified example:

File "import-for-extend.scss":
%to-extend { outline: 1px solid red; } .class1 { @extend %to-extend; }
File "test.scss":
@use "import-for-extend" as *; .class1 { @extend %to-extend; }
With this constellation the following error message appears:

Error: The target selector was not found.
Use "@extend %to-extend !optional" to avoid this error.

Of course extending something a second time makes no sense but it took a while in this large Sass project to find out the reason. I think the Sass message should be informing about this equal extendings not that the selector was not found.

[Awjin]

Sorry for the late reply here. This looks like an actual bug caused by @use's interaction with @extend.