Velcro!!!!

That stuff doesn't stick to most fabrics and is butter soft.
The worst offender is faux velcro……

Depends on what you want it to do, like with most everything else. A thin strip of "stick-to-itself velcro" is light as heck and so much easier to use for keeping open a tent door — as compared to pushing a plastic toggle through a cord loop.

What's "baby velcro" and where do you get it?

Sometimes I do curse at it when it tangles up and sticks together.
But! It's the lightest and best thing I've found for lashing my tent poles to the outside of my pack.

Fabric stores :-)
It doesn't have the coarseness of off brand Velcro. As well, even if one use non-baby Velcro, get the 'soft & flexible' type they make – it doesn't have the harsh edges.