iTunes protocol handler on Linux with Wine

Today I have tried adding my PayPal account to my iTunes (installed with Wine) Account but discovered, that adding my PayPal account as a payment method didn't work. After inspecting the network traffic, I found that my browser (Firefox) was redirected to an `itmss://` URL, but Firefox didn't know how to handle that and did nothing. To get it working yourself, follow the next steps:

Assuming you already have iTunes installed and are using Firefox, open `about:config` in Firefox, accept the prompt, right-click and select New -> Boolean. In the dialog enter `network.protocol-handler.expose.itmss` as preference name and select `false` as value. After that, restart Firefox.

Next, create a new file somewhere (I chose `/usr/local/bin/`), called for example `itunes-url` and make it executable (`chmod +x filename`). Put the following content into the file while adjusting the paths to the Wine prefix and the installation directory.

I found this invocation with Wine regedit.exe under `HKEY_CLASSES_ROOT\itmss\shell\open\command`, based on this website.

this website

Then you can go into iTunes and add your PayPal payment method. Once you've logged in and accepted the PayPal prompts, you should get a popup from Firefox where you should select the application to handle the `itmss` URL. Select the `itunes-url` script, you created before and click "Open link". Now iTunes should get the URL from PayPal and you can confirm the new payment method in iTunes.

Have fun!