Tags box: Add new tag before editor when Enter is pressed

Previously, when you clicked the Add button, typed a tag, and pressed Enter, the
new tag would be added *after* the now-empty editor field, putting the editor at
the top rather than the bottom.

chrome/content/zotero/elements/tagsBox.js

@@ -587,7 +587,7 @@
 			for (let editable of tagEditables) {
 				// Sort tags without colors below tags with colors
 				if (!color && this._tagColors.has(editable.value)
-						|| collation.compareString(1, tagName, editable.value) > 0) {
+						|| editable.value && collation.compareString(1, tagName, editable.value) > 0) {
 					continue;
 				}