[FP5] : Option to select Calling/Roaming preference under Use Wi-Fi calling is unavailable with Congstar (T-Mobile Germany)

• /e/ version: 1.15.2-t-20231011340157-stable-FP5
• Device model(s): FP5
• Developer mode enabled: yes
• Device rooted: no
• Trackers blocker enabled: yes

Summary

[FP5] : Option to select Calling/Roaming preference under Use Wi-Fi calling is unavailable with Congstar (T-Mobile Germany)

The problem

Steps to reproduce

• Navigate into Settings > Network and Internet > SIMs > Wi-Fi Calling

What is the current behavior?

• No option to enable :
  • Calling preference
  • Roaming preference

What is the expected correct behavior?

• All the options should be available as the user reported the same to be working on the stock FPOS.

Technical informations

Relevant logs (adb logcat)

Relevant screenshots

Airtel (India)	Congstar (T-Mobile Germany)

Solutions

Workaround

Possible fixes

/cc @nicofonk @rhunault @merothh