Tails - How to disable MAC address randomization?

I am trying out [Tails](https://tails.net/index.de.html) and disabled the [MAC address randomization](https://tails.net/doc/first_steps/welcome_screen/mac_spoofing/index.en.html#index5h1) feature during boot, but when doing ip addr in the terminal, the MAC address of wlan0 (WiFi adapter) keeps changing regardless. This is extremely annoying and means e.g. that I cannot access WiFi hotspots employing a MAC filter. Is there any way to disable this feature e.g. from a root terminal and force Tails to use a static MAC address?