Applying stroke for a non-grouped marqueed set of shapes removes fill from those objects (v25.3.1)
Just as the title says, selecting a set of non-grouped objects and applying a stroke that selection causes all of the fills in those shapes to be removed.
•Quad-Core Intel Core i7, 3.1 GHz
• Memory: 16 GB
• Mac OS Big Sur 11.4
• Illustrator v 25.3.1
Dan, is fixed in the next build, try it.