Visible lineweights in layouts

The other day, while I was working, the lines in one of my layouts ballooned out. It looks like the lineweights have been increased. I checked and they have not. This happened to some of the lines/text both on the layout and visible through the viewports. However, when I switch over to the model, the distortions are not visible. Also, I can print the layouts without any evidence that it is distorted. This appears to simply be visible on the monitor and only in the layout. This happened to me several months ago, too, but it was a much simpler drawing and I was able to work with it.

I hoped that the problem would go away with closing/reopening ACAD, but it remains, only on the one drawing, even after shutting down the PC, almost as if it is a property that was saved in the drawing.

Thanks, in advance, for any help.

The LWT button at the bottom of the screen is on, pick it once to turn it off in that drawing/layout.

Thanks! I figured it must be something dumb, but couldn't figure it out.