I was able to reproduce this. Apparently a new empty tag is being added to the options when selecting the tag with the keyboard:

<option value="#new#" selected="selected"></option>

Tested on Firefox v32.0.3

I also tested this on and old v3.3.0 and it's working fine

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Im looking into this in detail this evening.
The Issue is caused by the script in joomla-cms/cms/html/tag.php.

In my opinion that script needs refactoring not only because of the "saving article" bug.
The intended behaviour (select tag with keyboard, add new/custom tag with enter OR comma key) is not working properly (for instance: you cant add a custom tag, which begins with the same characters as an existing one).


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Please check #4398

The intended behaviour (select tag with keyboard, add new/custom tag with enter OR comma key) is not working properly (for instance: you cant add a custom tag, which begins with the same characters as an existing one).

Yes you can but to discard the proposed options you have to click the "up arrow".

Good job. I´ll test the fix later.
Nevertheless we could make some improvements to the script (i dont want to add a new tracker item for that).

1) When you add a new tag with comma, the comma doesnt get removed from the tag name ("myTag," instead of "myTag").

2) (Not that important). Change the chosen "no_results_text" to something that describes the possibility to add new tags with enter or comma. Chosen Documentation

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