Hi @Aayush_CU, welcome to the forum!
Could you try with Raspberry Pi 4? Because using more than 1 monitor feature is supported since webOS OSE 2.0 or later which only supports Raspberry Pi 4. (System Requirements | webOS Open Source Edition)
We do not guarantee that all features in webOS OSE 2.x are available on Raspberry Pi 3.
If you have to use Raspberry Pi 3, consider one of the following options:
- Use the final version of webOS OSE 1.x: GitHub - webosose/build-webos at @91.release
In this case, please refer to the 1.x version documentation. - Try Raspberry Pi 3 B+ using @jama 's tips: Raspberry Pi 3 b+ support? - #23 by jama
Thanks!