I'd like to be able to see (as in, read-only) some admin settings, even if allowAdminChanges is false.
For example, I want to check my SMTP details are correct, but I don't want to allow them to be changed since I want them controlled through the yaml.
Currently I'm changing allowAdminChanges to true, having a quick peek to check everything's in order, then setting it to false again, which isn't ideal.
For what it's worth, I'd suggest having read-only Settings section access be restricted to Admins only.
Is there any sort of ETA for this? 3.5? 4.0?
Would need to be 4.0 at the earliest, since plugins are also involved in showing their settings, and currently they don't have to worry about the possibility of a read-only mode.
Hmm... all those settings are saved in the Project Config, right? What about a stopgap solution where you allow admins to basically view the contents of project.yaml in some form or another, right in the backend? It doesn't need to be fancy, just functional. At the most rudimentary, perhaps a phpinfo()-style page that just prints out the project.yaml contents, where you can use native browser search to find the setting you're interested in?
A very useful enhancement to something like that would be to present that raw project.yaml info hierarchically, in an accordion (<details> & <summary>, perhaps?) or something. Add a simple "Expand all" / "Collapse all" button at the top to allow in-page browser searching, and that's it.
¯\_(ツ)_/¯
I don’t think the settings views should look significantly different when admin changes are disabled. Maybe we could introduce a new “Project Config” utility instead, similar to PHP Info.
That would definitely suffice for me! :)
Does it also make sense to have the Craft log files viewable via the backend? I could certainly stand to have that functionality on a production site I'm working on right now (GUI DB backup failed, said to check Craft logs for details, but I don't have access to the load-balanced servers...).
We’ve added a new Project Config utility for the next Craft 3.5 beta release! In addition to giving you a dump of the current project config data, it also provides handy access to a couple project config maintenance actions.

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We’ve added a new Project Config utility for the next Craft 3.5 beta release! In addition to giving you a dump of the current project config data, it also provides handy access to a couple project config maintenance actions.