A separate "Show All" button would allow for mouse-only interaction in the rare cases where this could be needed, and the placeholder text could be updated to "Search or add" to make "add" more discoverable.

This would also make it easier to set a minimum number of characters to type before search results are shown, to limit the maximum amount of rows for the more common use cases.

My recommendations:

• "Show All" button - when pressed it will do same work as pressing ESC keyboard button, it could hide itself after showing all
• "New" button - when pressed it will show dropdown menu with 3 items: "String", "Integer", "Boolean"

Attaching some mockups done in Paint.

It's kinda odd for me that adding 2 simple buttons could cause any performance issues and about design it can always be changed for better accessibility, efficiency and discover purposes.

The performance issue is not the button, but the "show all" functionality. That is why Paolo wants to "hide" it a bit better.
Dropdowns are not design-able to be consistent with the photon guide, that is why we were trying to build the page without them.

This allows interacting with the page without using the keyboard in the rare cases where this may be necessary. The separate button is ghosted and placed at the bottom of the page because search is the preferred interaction.

To improve performance, search is now activated automatically only after typing at least 3 characters. Pressing ESC allows resetting the input field without the performance impact of showing all preferences.

This patch replaces the "Search or press ESC to show all" placeholder with a separate "Show All" button, and the placeholder becomes "Search or add". Mike thought the placeholder could say "Search or add preferences" for clarity, although I think it's a bit redundant given that this is the "about:config" page anyways. Amy, what do you think of these new strings?

https://hg.mozilla.org/mozilla-central/rev/329374773b81

(In reply to :Paolo Amadini from comment #11)

This patch replaces the "Search or press ESC to show all" placeholder with a separate "Show All" button, and the placeholder becomes "Search or add". Mike thought the placeholder could say "Search or add preferences" for clarity, although I think it's a bit redundant given that this is the "about:config" page anyways. Amy, what do you think of these new strings?

I think it doesn't hurt to be clear and have "Search or add preferences". NI Meridel to approve strings.

I don't think "add preferences" is necessary and could be confusing.

I don't like the idea of just "Search preferences" because I'd like to distinguish between the about:config preferences versus the preferences users access from the hamburger menu.

I'm not a regular user of about:config. What kind of language do about:config users use when talking about modifying things in about:config? I am thinking something like "Search browser settings" or "Search configuration preferences" would distinguish this set of Preferences from the hamburger menu preferences, and be a bit more accurate.

Could someone on this bug enlighten me as to what language regular users of about:config use to describe the actions they take? Do they think of this as adjusting settings or preferences? and, are these browser settings/preferences or something else?

The technical term used for "about:config" is "preferences", and it is the same on Windows, Mac, and Linux. The menu item that gives access to "about:preferences" is instead called "options" on Windows and "preferences" on other platforms.

The expressions "set a preference", "toggle a preference", or "pref flip" are common among regular "about:config" users. I don't think there is any chance of confusion between "about:config" and "about:preferences". That said, I'm comfortable with calling the textbox just "Search" and omitting the object altogether.

Thank you. Recommended strings:

Search field string: Search advanced preferences
Show all button string: Show All Preferences

Question: Does Escape still enable me to see all preferences? It no longer works for me but does work for a colleague of mine. If so, I would adjust copy.

No, the ESC key only clears the text box now, which goes back to the initial state.