?

Bleach solution works well. If you can lift the doors off, then you pry it up and soak the plastic in the sink. Otherwise spay it on. Use a tooth brush to scrub off the plastic.

You may find it necessary to dry this space after showers, using a microfiber towel. If you don't have a very powerful bath exhaust fan with automatic humidity sensor, you may want to consider installing one. It automatically turns on and shuts off without you having to worry about it.

I find this product works well for tubs/shower plastic strip guides: https://amzn.to/2ZPWLlx

Hope this Helps! Jeremy - https://pahjodesigns.com

Chlorax for sure will do the work but if mold is growing that means you don't have a good ventilation. I would make sure your shower doors are open after you take a shower and for sure install a better fan in the bathroom

Soak paper towels or cloths in white cleaning vinegar and sit, let soak.

You generally need to get under the edge to clean. Moisture is getting trapped in a warm environment and you get mold. Once you get it clean (I like Scrubbing bubbles), you need to make sure there is air circulation to dry it out after a shower. Even a box fan can help. Good luck and stay safe!