Trusted domain editor: Looks like text file, but isn't

[aeschli]

Testing #80595

• invoke Manage Trusted Domains
• any changes to the file are lost, only the values are kept. e.g. my formatting, commented out domains.

[octref]

Good catch, makes sense.

To verifiers:

Verify that:

• Manage Trusted Domains setting should preserve your commented out parts
• When you have removed the header or end, for example by deleting the first line // Links matching one or more entries in the list below can be opened without link protection. or last line // Save this file to apply the trusted domains rules., the next time you run Manage Trusted Domains it'll be restored.