There is a clear plastic sticky material called museum putty that museums use to prevent their display objects from sliding around on shelves.
They place a lozenge of the material on the bottom of the object and it holds it well enough, but is easy to move and re-place the items, as necessary...
We have C21 dimmers and Strand makes modules that are true non-dims and also (my favorite) modules that have a switch on front that allows them to be true non-dims or dimmers, as necessary.
One comment correctly stated that intelligent fixture manufacturing folks don't recommend powering their...