diff --git a/phpBB/assets/javascript/core.js b/phpBB/assets/javascript/core.js
index c40852388e..17e859eedc 100644
--- a/phpBB/assets/javascript/core.js
+++ b/phpBB/assets/javascript/core.js
@@ -417,8 +417,19 @@ phpbb.ajaxify = function(options) {
 * @param	bool	keep_selection		Shall we keep the value selected, or shall the user be forced to repick one.
 */
 phpbb.timezone_switch_date = function(keep_selection) {
-	$('#timezone > optgroup').css('display', 'none');
-	$("#timezone > optgroup[label='" + $('#tz_date').val() + "']").css('display', 'block');
+	if ($('#timezone_copy').length == 0) {
+		// We make a backup of the original dropdown, so we can remove optgroups
+		// instead of setting display to none, because IE and chrome will not
+		// hide options inside of optgroups and selects via css
+		$('#timezone').clone().attr('id', 'timezone_copy').css('display', 'none').attr('name', 'tz_copy').insertAfter('#timezone');
+	} else {
+		// Copy the content of our backup, so we can remove all unneeded options
+		$('#timezone').replaceWith($('#timezone_copy').clone().attr('id', 'timezone').css('display', 'block').attr('name', 'tz'));
+	}
+
+	if ($('#tz_date').val() != '') {
+		$('#timezone > optgroup').remove(":not([label='" + $('#tz_date').val() + "'])");
+	}
 
 	if ($('#tz_date').val() == $('#tz_select_date_suggest').attr('data-suggested-tz')) {
 		$('#tz_select_date_suggest').css('display', 'none');
@@ -488,18 +499,20 @@ phpbb.timezone_preselect_select = function(force_selector) {
 			if ($('#tz_date').val() != option.value && !force_selector) {
 				// We do not select the option for the user, but notify him,
 				// that we would suggest a different setting.
-				$('#tz_select_date_suggest').css('display', 'inline');
-				$('#tz_select_date_suggest').attr('title', $('#tz_select_date_suggest').attr('data-l-suggestion').replace("%s", option.innerHTML));
-				$('#tz_select_date_suggest').attr('value', $('#tz_select_date_suggest').attr('data-l-suggestion').replace("%s", option.innerHTML.substring(0, 9)));
-				$('#tz_select_date_suggest').attr('data-suggested-tz', option.innerHTML);
 				phpbb.timezone_switch_date(true);
+				$('#tz_select_date_suggest').css('display', 'inline');
 			} else {
 				option.selected = true;
 				phpbb.timezone_switch_date(!force_selector);
-				$('#tz_select_date_suggest').attr('data-suggested-tz', option.innerHTML);
 				$('#tz_select_date_suggest').css('display', 'none');
 			}
-			break;
+
+			$('#tz_select_date_suggest').attr('title', $('#tz_select_date_suggest').attr('data-l-suggestion').replace("%s", option.innerHTML));
+			$('#tz_select_date_suggest').attr('value', $('#tz_select_date_suggest').attr('data-l-suggestion').replace("%s", option.innerHTML.substring(0, 9)));
+			$('#tz_select_date_suggest').attr('data-suggested-tz', option.innerHTML);
+
+			// Found the suggestion, there cannot be more, so return from here.
+			return;
 		}
 	}
 }
diff --git a/phpBB/styles/prosilver/template/timezone_option.html b/phpBB/styles/prosilver/template/timezone_option.html
index 94e2bbdfbd..24d6aa677f 100644
--- a/phpBB/styles/prosilver/template/timezone_option.html
+++ b/phpBB/styles/prosilver/template/timezone_option.html
@@ -6,7 +6,7 @@
 			<option value="">{L_SELECT_CURRENT_TIME}</option>
 			{S_TZ_DATE_OPTIONS}
 		</select>
-		<input id="tz_select_date_suggest" class="inputbox button2" style="display: none; width: 150px !important;" data-is-registration="<!-- IF S_REGISTRATION -->true<!-- ELSE -->false<!-- ENDIF -->" data-l-suggestion="{L_TIMEZONE_DATE_SUGGESTION}" value="fuu" />
+		<input type="button" id="tz_select_date_suggest" class="button2" style="display: none;" data-is-registration="<!-- IF S_REGISTRATION -->true<!-- ELSE -->false<!-- ENDIF -->" data-l-suggestion="{L_TIMEZONE_DATE_SUGGESTION}" value="{L_TIMEZONE_DATE_SUGGESTION}" />
 	</dd>
 	<!-- ENDIF -->
 	<dd>
diff --git a/phpBB/styles/subsilver2/template/timezone_option.html b/phpBB/styles/subsilver2/template/timezone_option.html
index 3f1e14b33d..c7e47a8ee4 100644
--- a/phpBB/styles/subsilver2/template/timezone_option.html
+++ b/phpBB/styles/subsilver2/template/timezone_option.html
@@ -7,7 +7,7 @@
 				<option value="">{L_SELECT_CURRENT_TIME}</option>
 				{S_TZ_DATE_OPTIONS}
 			</select><br />
-			<input id="tz_select_date_suggest" class="btnlite" style="display: none;" data-is-registration="<!-- IF S_REGISTRATION -->true<!-- ELSE -->false<!-- ENDIF -->" data-l-suggestion="{L_TIMEZONE_DATE_SUGGESTION}" value="{L_TIMEZONE_DATE_SUGGESTION}" />
+			<input type="button" id="tz_select_date_suggest" class="btnlite" style="display: none;" data-is-registration="<!-- IF S_REGISTRATION -->true<!-- ELSE -->false<!-- ENDIF -->" data-l-suggestion="{L_TIMEZONE_DATE_SUGGESTION}" value="{L_TIMEZONE_DATE_SUGGESTION}" />
 		</div>
 		<!-- ENDIF -->
 		<select name="tz" id="timezone" class="autowidth tz_select">