1<===> input.scss
2.bar {
3  @extend .foo;
4  color: green;
5}
6<===> error
7Error: ".bar" failed to @extend ".foo".
8       The selector ".foo" was not found.
9       Use "@extend .foo !optional" if the extend should be able to fail.
10        on line 2 of input.scss
11  Use --trace for backtrace.
12
13<===> error-libsass
14Error: The target selector was not found.
15       Use "@extend .foo !optional" to avoid this error.
16        on line 2 of input.scss
17>>   @extend .foo;
18   ----------^
19
20<===> error-dart-sass
21Error: The target selector was not found.
22Use "@extend .foo !optional" to avoid this error.
23  ,
242 |   @extend .foo;
25  |   ^^^^^^^^^^^^
26  '
27  input.scss 2:3  root stylesheet
28