I'm updating a few of my roller blinds from recess fit to face fit. Motivated by too much light in the early morning at this time of year. Face fit means the entire window is covered.

I had some weird idea face fit blinds optionally use a guide wire to keep them snug against the face and prevent light bleed. I've googled around and seen nothing like that from local merchants.

Am I imagining or is this a common thing I can't find?