Prolly around 8 years ago, I attempted to dim an non dimmable Feit yellow spiral bug lite CFL in an gooseneck desk lamp, started with dimmer set at full brightness, while adjusting, the CFL spiral tube on one side close to base blew away where the electrode would be and that CFL was done for but the dimmer I used suffered no damage. The dimmer I made this attempt with is one of them X-10 home automation lamp dimmer modules that are rated for 300 watts maximum incandescent only. An X-10 command console controller is needed with these plug in modules.

From 240V-world : Above some setting they stay at about the same brightness. Below that setting they flicker. Way below they stay off

I have not played with then enough to see any damage, but i can guess the input filtering cuircuit in the CFL - 4 diodes and capacitor - won't like the shorter charging impulses caused by the dimmer (as the capacitor charges up to the same peak voltage in shorter time = higher current peaks heating everything up). With the components used in CFLs (marginally sufficient for 1 lamp life) it is allready on the edge the way it is without the dimmer