Keychron low-profile inline stabilizer

Drop-in replacement of the original stabilizer housing. Allows for use of standard MX keycaps in Keychron low-profile keyboards.

Tested on Keychron K1 v5 with Keychron Optical switches.

### Why WIP?

I'm dissatisfied with how one of my keys works—it's slightly mushy and sticky.

Other than that, four out of five keys are running OK—they are fully operational, but far from "premium feel".

### About stems

I recommend cutting out a small chunk of the original stem with an exacto knife (check the pictures). Without this mod, the stems will hit the edge of the PCB, reducing the key's travel distance and adding unpleasant noise when the key is bottoming out.

You can also try to print and use the attached stems, but I wasn't satisfied with them. Due to the nature of the stem's cross shape, I've printed them upwards, which introduces 2 problems:
- Grinding noise due to motion perpendicular to parallel layers on both parts.
- Higher risk of stem breaking off and clogging the keycap mountin