How To Forward chase (50% white) - Reverse chase (100%)

Hi everyone, I am planning a project with a 20-meter LED strip (96 LEDs/m, roughly 1920 LEDs total) controlled by WLED on an ESP32. I would like to implement a specific startup sequence and I am looking for the best way to achieve it.

When triggered by homeassistant, the LEDs should first run a forward chase from the beginning to the end, turning each LED on to 50% white brightness. Once it reaches the end, a reverse chase should run all the way back to the start, increasing the brightness of the LEDs to 100%. After this second pass finishes, the entire strip should stay permanently ON at full white brightness.

How would you recommend setting this up in WLED? spent a lot of time trying to set this up using standard Presets and Playlists, but I couldn’t get it to work properly. Maybe json api is the best way but also there i don’t get a positive result.
Thanks in advance for any tips!

use two overlapping segments and add them

I tried, but somehow it’s not working for me as expected. :confused:

Could you perhaps create a playlist for me and then send the code so I can see what I’m doing wrong, or send a few pictures please?