User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.88 Safari/537.36

Steps to reproduce:

1. Install "Add custom search engine" addon (https://addons.mozilla.org/en-US/firefox/addon/add-custom-search-engine/).
2. Using the addon, add a new search engine and name it with a comma sign (","). The name can be anything, as long as it includes a comma.
3. Untick that search engine in "One-Click Search Engines" of "about:preferences#search".
4. Refresh "about:preferences#search".

Alternatively, a search engine (that has a comma in the name) also can be installed from mycroftproject.com; this is still supported in stable v77.

Actual results:

The search engine is still ticked.
The name can be "foo, bar" or even just a single comma ",", the result is still the same.

Expected results:

The search engine should remains unticked and hidden from the address bar.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

The severity field is not set for this bug.
:daleharvey, could you have a look please?

For more information, please visit auto_nag documentation.

Checked issue and is reproducible in all Os and all versions

Windows10 64bit, Ubuntu 18.04 64bit and macOs 10.15
Using firefox Release 77.0.1, Beta 78 and Nightly 79.0a1

• launch firefox
• install addon https://addons.mozilla.org/en-US/firefox/addon/add-custom-search-engine/
• in addon , add search "biin," (it has a comma at the end), and link "https://www.bing.com/search?q=selenium"
• go to about:preferences#search
• Uncheck "biin," from one click engines
• refresh page> biin, becomes checked again.

It has been this way for a long time - the preference that stores this is a comma-separated list of values (browser.search.hiddenOneOffs)

We should probably just move it into the cache and have it as a flag on the search engine object. It'd also make it better as then all the data would be stored together.

https://hg.mozilla.org/mozilla-central/rev/52f0232ceb58