gui2/ttext_: Disable blinking cursor

There's an issue with textboxes across separate window instances (e.g.
when firing up the New Folder dialog in the file dialog) each getting a
blinking cursor simultaneously displayed on the screen due to timer
events persisting even when a GUI2 window isn't running. This may cause
repaint issues since the whole textbox may need to be redrawn each time
the timer fires, so it's best to disable it until I figure out a better
way to implement a unique global blinking cursor.

data/gui/widget/text_box_default.cfg

@@ -66,7 +66,8 @@
 		x2 = "(cursor_offset + {X_OFFSET})"
 		y2 = "(text_y_offset + text_font_height - 2)"
 		color = "255, 255, 255, 255"
-		alpha = "(cursor_alpha)"
+		# TODO: disabled until there's a way to deal with textboxes on multiple windows
+		#alpha = "(cursor_alpha)"
 		thickness = 1
 	[/line]
 #enddef

src/gui/widgets/text.cpp

@@ -40,7 +40,7 @@ ttext_::ttext_()
 	, selection_length_(0)
 	, cursor_timer_(0)
 	, cursor_alpha_(0)
-	, cursor_blink_rate_ms_(750)
+	, cursor_blink_rate_ms_(0) // TODO: disabled until there's a way to deal with textboxes on multiple windows
 	, text_changed_callback_()
 {
 #ifdef __unix__
@@ -254,6 +254,10 @@ void ttext_::set_state(const tstate state)
 
 void ttext_::toggle_cursor_timer(bool enable)
 {
+	if(!cursor_blink_rate_ms_) {
+		return;
+	}
+
 	if(cursor_timer_) {
 		remove_timer(cursor_timer_);
 	}
@@ -285,6 +289,10 @@ void ttext_::cursor_timer_callback()
 
 void ttext_::reset_cursor_state()
 {
+	if(!cursor_blink_rate_ms_) {
+		return;
+	}
+
 	cursor_alpha_ = 255;
 
 	for(auto& tmp : canvas()) {