Proprietary tile isn't ideal

The new proprietary tile (as discussed in #1349 (closed)) doesn't quite work:

• The gray icons don't work because there's no obvious valence to the tile anymore. Without the color the tile feels random and doesn't communicate anything at a glance. If we absolutely want to avoid red I'd go with yellow here. => #1835 (closed)
• The icons need another pass, I'll look into that. => #1835 (closed)
• There may be restrictions on its use and it may be harder to tell if it's insecure is too vague, and the multiple conditionals sound very lawyer-y. I'd go with something simpler and more direct, e.g. It may be insecure or do harmful things in ways that are hard to detect.
• You may not be able to contribute to this software or influence its development. doesn't really add anything in its current form IMO. I think we could just drop that sentence.
• The original label had a sentence about trust which I felt was relevant for proprietary apps since you're running a random binary with little possibility of outside review. That seems like an important practical difference to free software apps.

For reference, the original text:

This app is not developed in the open, so only its developers know how it works.
It could be insecure, or actively do nefarious things that are hard to detect or prevent.

By installing this app you are putting a high amount of trust in the developers.