GL-AR300M Wifi Button

I use my router primarily to connect a phone, which means I usually don’t need Wifi. However, there have been some occasions in which I either needed to connect another device or just wanted/needed to access the router with my smartphone.
The solutions to utilize the slide switch to turn wifi on/off don’t work (at least not without deeper knowledge).
Has anyone a solution that works for a recently purchased router?

Check that the Button is correctly set on MORE SETTINGS → Button Settings.

In my admin-panel there is no option for switching on/off Wifi using the switch. I would love to have that.
The config files that the older solution are referring to look totally diferent than what I found on the router, so I have no idea how these solution can solve the problem. For example my initswitch file only has some lines of code, meaning there is neither a line 57 nor a line 70, as suggested in this post FEATURE REQ: WiFi on/off with side switch? - #6 by alzhao

The script may change according to different firmware version. But how it works are the same.