The Glock requires so little lubrication anyway that you are unlikely to attract any significant amount of dirt that would stop the functioning of the pistol. I'd stick with BreakFree CLP.
1 drop on each slide rail. 1 drop under barrel locking lug. 1 drop in the trigger assembly where the trigger bar and connector slide against each other.
BreakFree CLP is still the most likely of all lubricants to overcome any amount of dust/dirt it attracts. Military tests have proven this.
If you ABSOLUTOLEY just don't want to use BF CLP and don't want to attract dust, go with Mil-comm TW-25B. This stuff will stay where you put it, and if you wipe it off it still lubes nicely and won't attract dirt. You do have to follow the application instructions though, all traces of previous lube must be wiped off with alcohol and Mil-comm MC-25 cleaner so that the TW-25B can bond with the metal. It also protects from rust almost as good as CLP.
Avoid Militec-1 incase anyone has recommended it to you. It does nothing to protect against rust and in the military's own tests it had more jams than just running the firearm dry.
Eezox is also another very good CLP, I find it's not as good of a lube as BF CLP, but it is a better protectant. However BF CLP does plenty to protect and unless you plan on storing your firearms for 5+ years without reapplication, Breakfree is probably the better choice. It is wet just like BF CLP and therefore probably will attract dust.
I've done my own lab tests on BF CLP, Eezox CLP, TW-25B, MC-2500, and Militec-1 to test for lubrication effectiveness, protection from rust, restistance to heat, human handling, long-term staying ability, and dust attraction (and lubricity after dirt/dust attraction). BreakFree CLP came out tops for all-purpose including dust. TW-25B thick for marine environments. Eezox for long term storage.