[HP Spectre x360] Decryption prompt not showing up without external display connected

[therealchfkch]

Distribution (run cat /etc/os-release):
22.04 LTS

Issue/Bug Description:
On my laptop (HP Spectre x360), i installed Pop_OS with default/automatic partitioning and disk encryption. After installing i used Pop_Shop to install the latest updates. After rebooting i get a black screen.

Steps to reproduce (if you know):
Installing and updating lead this behavior. I have not tried installing and not updating though.

Expected behavior:
After rebooting, i expected the decryption dialog to show.

Actual behavior:
After rebooting, the screen is black. Pressing Escape twice as suggested #2170 did not help.
Anyway, I could just type in the password blindly and hit Enter to input my password. This unlocks the encryption and redirects me to the (GNOME) user login.
What helped to get the dialog visible is to plug in an external monitor. This mirrors the laptop screen (not extending it). If u remove the monitor before decrypting, the laptop screen goes black again.

Other Notes:
If i need to attach some info from dmesg or something, let me know since this is my first issue i open.

[therealchfkch]

Just a side note: i have a NVIDIA card in the laptop.
The described behavior happens either with NVIDIA drivers installed on the OS or with the "normal" drivers and the Intel integrated graphics card.