Fix tunnel build viewport length tooltip when hover mode is right click

src/misc_gui.cpp

@@ -774,6 +774,7 @@ struct TooltipsWindow : public Window
 			case TCC_RIGHT_CLICK: if (!_right_button_down) delete this; break;
 			case TCC_LEFT_CLICK: if (!_left_button_down) delete this; break;
 			case TCC_HOVER: if (!_mouse_hovering) delete this; break;
+			case TCC_NEXT_LOOP: this->delete_next_mouse_loop = true; break;
 
 			case TCC_HOVER_VIEWPORT:
 				if (_settings_client.gui.hover_delay_ms == 0) {

src/viewport.cpp

@@ -3783,7 +3783,7 @@ void VpSetPresizeRange(TileIndex from, TileIndex to)
 	_thd.next_drawstyle = HT_RECT;
 
 	/* show measurement only if there is any length to speak of */
-	if (distance > 1) ShowMeasurementTooltips(STR_MEASURE_LENGTH, 1, &distance, TCC_HOVER);
+	if (distance > 1) ShowMeasurementTooltips(STR_MEASURE_LENGTH, 1, &distance, _settings_client.gui.hover_delay_ms == 0 ? TCC_NEXT_LOOP : TCC_HOVER);
 }
 
 static void VpStartPreSizing()

src/window_gui.h

@@ -924,6 +924,7 @@ enum TooltipCloseCondition {
 	TCC_LEFT_CLICK,
 	TCC_HOVER,
 	TCC_HOVER_VIEWPORT,
+	TCC_NEXT_LOOP,
 };
 
 void GuiShowTooltips(Window *parent, StringID str, uint paramcount = 0, const uint64 params[] = NULL, TooltipCloseCondition close_tooltip = TCC_HOVER);