System profile automatically chooses secondary SIM for cellular data

• /e/ version: 0.23-r-20220404175826-dev-FP3
• Device model(s): Fairphone 3
• Device rooted: no

When configuring a system profile to activate cellular data, Android automatically chooses the secondary SIM card for that – even though I always use the primary one. There doesn't seem to be a way to change that. When manually activating the cellular data via the primary SIM card, a confirmation dialogue appears, meaning that the general default SIM card has probably been changed to the secondary one.