It seems unifying Windows Phone and Windows has drawn the attention of people with some special skills, as the hacks involving the OS just keeps rolling in.
The latest is a partial jailbreak/Interop unlock of the OS which lets you do things such as write to anywhere in the file system or write to a large number of registry keys and remove limits to the number of apps you can side load for example.
The instructions are also pretty simply,being:
1. Turn “ON” Developer Unlock Mode. (Go to Settings> Update & Security> For Developers)
2. Download “Root Tool.xap” from here and deploy It.
Open “vcReg” Tool.
Hit the Application Bar and select “Templates”.
Here will see two options, Interop/Capability Unlock and “Full File System” Access through the MTP Protocol.
Check your options, and click “Apply”.
The hack at present only works on Lumia and Samsung Windows 10 Mobile handsets (both 10166 and 10512) and has already been used to alter the Hosts file in Windows Mobile to block ads in the browser, which is an interesting application.
Read full instructions and find the downloads at XDA-Developers here.
Thanks DontAsk for the tip.