Fixes issues of #17255. Fix tab sequence (#17256)

* fixes issus #17252. a11y improvements. fix Talkback item selection. i18n for the status text.

* fixes issues of #17252. a11y improvements. fix Talkback item selection. i18n for the status text.

* Make aria-activedescendant empty when none is selected. see w3c/aria#501 (comment)

* Make aria-activedescendant empty when none is selected. see w3c/aria#501 (comment)

* Transformation must end with visibility hidden. Fixes tab navigation to hidden li item

* Also in css leading tab characters. After css transition everything in the suggestion list must be hidden and for example links in suggestions should not be in the tab sequence anymore

* Fixes issue of #17255. Tab navigation when suggestions are shown is wrong

---------

Co-authored-by: Nico <[email protected]@users.noreply.github.com>

awesomplete.js

@@ -195,6 +195,7 @@ _.prototype = {
 		this.index = -1;
 
 		this.status.setAttribute("hidden", "");
+		this.input.setAttribute("aria-activedescendant", "");
 
 		$.fire(this.input, "awesomplete-close", o || {});
 	},
@@ -345,6 +346,8 @@ _.prototype = {
 				this.close({ reason: "nomatches" });
 
 			} else {
+				this.input.setAttribute("aria-activedescendant", ""); // none of the list items currently has aria-selected="true"
+
 				this.open();
 
 				this.status.textContent = this.statusXResults.replaceAll('{0}', this.ul.children.length); // N results found;
@@ -397,7 +400,7 @@ _.ITEM = function (text, input, item_id) {
 		innerHTML: html,
 		"role": "option",
 		"aria-selected": "false",
-		"tabindex": '0', // for the Talkback screen reader
+		"tabindex": "-1", // for the Talkback screen reader
 		"id": "awesomplete_list_" + this.count + "_item_" + item_id
 	});
 };