Why do my face sets have holes in them?

Question

I'm sculpting a character in Blender, and I'm attempting to hide parts of it using face sets. When I use the Draw Face Sets tool, the face set appears to have holes in it:

For reference, the topology of the sculpt looks like this:

And when I hide everything but the face set, it looks like this:

I use Dyntopo to control the exact amount of detail throughout certain parts of the sculpt, but I can't seem to draw face sets at all unless I temporarily disable it.

Can anyone pinpoint the cause of this? Thanks in advance!

Update: It looks like I can make perfectly good face sets using Box Face Set, but still not with Draw Face Sets. Why is this?

Answer 1

(Please read the update at the end of this post btw)

I found two solutions!

The first solution I discovered was setting Propagation Steps to anything higher than 1.

Checking Topology under Auto-Masking had the same effect!

Now I can draw solid face sets.

Update: I think i just found the true underlying issue here. I realized that I couldn't "extend" face sets by holding ctrl, nor could I smooth them out using shift. I created a new file and experimented with a subdivided default cube in attempt to trace back to the root of the problem.

First, uncheck everything under Brush > Advanced > Auto-Masking, like so:

No need to increase Propagation Steps unless you know what you're doing (I don't).

Next, under Options in the top right of the Viewport, ensure that everything under Auto-Masking is unchecked.

You're all set! Draw Face Sets should function normally, exactly as it would in a fresh .blend file.