I use this method all the time with new games if the lights keep popping out of the spotlights. It works 100% of the time in my experience, and the bulbs never fall out again. It's WAY cleaner-looking than silicone or hot glue, IMO. You can't see anything is different once the bulb is installed. I'm showing a random LED bulb I grabbed to demonstrate this in the picture series, but it works for the LED flashers, too.

You need to cut a small piece of black electrical tape about the length of the bulb, and about half the width the electrical tape comes on the roll.
bulb-1 (resized).jpg
Then, carefully lift up the two "legs" of the bulb to get them out of the way.
bulb-2 (resized).jpg
Wrap the tape around both sides of the bulb, sticky side of the tape towards the bulb base.

Fold the two raised "legs" gently back down over the tape.
bulb-3 (resized).jpg

Put the bulb back in the spotlight or socket for likely the last time. It will grab a LOT better and likely never come out on its own from vibration again.

All done with this project? Here's a couple other DIY guides I've made for newer Spike machines:

How about a pool noodle to protect your playfield glass when it's off the machine:
https://pinside.com/pinball/forum/topic/pool-noodle-protector-for-playfield-glass-when-off-the-machine#post-6961597

Targets refusing to drop sometimes when you hit them? Fix that...
https://pinside.com/pinball/forum/topic/fix-for-bricking-targets-that-will-not-easily-fall-on-sterns#post-7696752

Have a Stern machine from KISS or after with the softer wood cabinet? Reinforce it to prevent a splitting cab:
https://pinside.com/pinball/forum/topic/reinforcing-stern-cabinet-legs-step-by-step

Want to have the option of operating the action button on your spike game with a foot pedal?
https://pinside.com/pinball/forum/topic/action-button-foot-pedal-for-bksor-godzilla-etc#post-6616394

Have an $80 alibaba hologram fan topper you want to cleanly power so it turns on and off with the machine? Do this:
https://pinside.com/pinball/forum/topic/hologram-fan-or-lightedpinballmods-power-fix#post-6241182

Are your Iron Maiden speakers crackling when you crank it up? Fix that with a cheap external amp:
https://pinside.com/pinball/forum/topic/replacing-on-board-amp-with-external-amp-for-iron-maiden

Add a working lockdown bar button to your Iron Maiden
https://pinside.com/pinball/forum/topic/iron-maiden-how-to-add-a-working-lockdown-bar-button

Deadpool Katana entrance protection:
https://pinside.com/pinball/forum/topic/protecting-katana-lane-entrance-from-playfield-damage

Is your Spike machine occasionally resetting during hectic play, torpedoing your high score runs? This guide to fixing it might be for you:
https://pinside.com/pinball/forum/topic/fixing-stern-reboots-on-spike

Do you have a WoZ ECLE and think it's too loud in a quiet room? Replace two fans and make it almost silent:
https://pinside.com/pinball/forum/topic/quieting-down-a-woz-ecle-machine

And here are some other plug and play mods you can just buy:
Iron Maiden Light Tree Mod for colored mode lights:
https://pinside.com/pinball/forum/topic/iron-maiden-colored-mode-lens-tree-mod

Metallica F-U-E-L lights bracket:
https://pinside.com/pinball/forum/topic/metallica-f-u-e-l-gauge-lens-bracket

ColorDMD gasket for Stern machines with the angled speaker panel:
https://pinside.com/pinball/forum/topic/colordmd-gasket-for-angled-stern-speaker-panels

Electrical tape method is completely foolproof. You can't smear the tape or squeeze too much on. Plus most people have electrical tape around the house. Not true for RTV silicone.

Relatively, but others have had them, too. Uglier than the electrical tape fix, IMO.

But you CAN see them. I personally prefer a cleaner look.

No problem. It is VERY nice not to have them popping out mid-game.

Just an update that this method also works for non-spotlight LED GI lighting bulbs that wiggle up and out of their sockets. Just did some GI bulbs that kept wiggling out of an AC/DC's GI recently and it worked great.

Dunno what electrical tape you're buying, but it takes at LEAST 10 years for the stuff I use to just begin to get gummy and brittle.

That said, shrink could work as long as it's not too tight to the bulb. Clips and glue are ugly crap for spotlights.

Try the shrink tubing and report back!

The mutants clearly aren't above playing dirty.

Probably get more suggestions for spinner rubber replacement ideas in the AIQ owner's thread.

Should be the last time you have the issue. I've only ever had one fall out after doing this, but I did it again and that one never fell out again. It's very reliable, easy, and essentially invisible.