diff --git a/distribution/changelog.txt b/distribution/changelog.txt
index 082a3fa131..fadac0c700 100644
--- a/distribution/changelog.txt
+++ b/distribution/changelog.txt
@@ -26,6 +26,7 @@
 - Change: [#8718] No longer require the generic scenery groups and tarmac footpath to be checked when creating a scenario.
 - Change: [#8734] Disable kick button in multiplayer window when unable to use it.
 - Fix: [#3832] Changing the colour scheme of track pieces does not work in multiplayer.
+- Fix: [#4094] Coasters with long flat-to-steep pieces offer them in diagonal mode (original bug).
 - Fix: [#5684] Player list can desync between clients and server and can crash.
 - Fix: [#6191] OpenRCT2 fails to run when the path has an emoji in it.
 - Fix: [#7439] Placement messages have mixed strings
diff --git a/src/openrct2-ui/windows/RideConstruction.cpp b/src/openrct2-ui/windows/RideConstruction.cpp
index 26e2339901..10e38925a0 100644
--- a/src/openrct2-ui/windows/RideConstruction.cpp
+++ b/src/openrct2-ui/windows/RideConstruction.cpp
@@ -139,6 +139,7 @@ static void window_ride_construction_toolupdate(rct_window* w, rct_widgetindex w
 static void window_ride_construction_tooldown(rct_window* w, rct_widgetindex widgetIndex, int32_t x, int32_t y);
 static void window_ride_construction_invalidate(rct_window *w);
 static void window_ride_construction_paint(rct_window *w, rct_drawpixelinfo *dpi);
+static bool track_piece_direction_is_diagonal(const uint8_t direction);
 
 //0x993EEC
 static rct_window_event_list window_ride_construction_events = {
@@ -837,7 +838,8 @@ static void window_ride_construction_resize(rct_window* w)
     switch (_previousTrackSlopeEnd)
     {
         case TRACK_SLOPE_NONE:
-            if (_currentTrackCurve != TRACK_CURVE_NONE)
+            if (_currentTrackCurve != TRACK_CURVE_NONE
+                || (is_track_enabled(TRACK_SLOPE_STEEP_LONG) && track_piece_direction_is_diagonal(_currentTrackPieceDirection)))
             {
                 disabledWidgets |= (1ULL << WIDX_SLOPE_DOWN_STEEP) | (1ULL << WIDX_SLOPE_UP_STEEP);
             }
@@ -847,7 +849,9 @@ static void window_ride_construction_resize(rct_window* w)
             break;
         case TRACK_SLOPE_DOWN_60:
             disabledWidgets |= (1ULL << WIDX_SLOPE_UP) | (1ULL << WIDX_SLOPE_UP_STEEP);
-            if (!is_track_enabled(TRACK_SLOPE_LONG) && !is_track_enabled(TRACK_SLOPE_STEEP_LONG))
+            if (!is_track_enabled(TRACK_SLOPE_LONG)
+                && !(is_track_enabled(TRACK_SLOPE_STEEP_LONG)
+                     && !track_piece_direction_is_diagonal(_currentTrackPieceDirection)))
             {
                 disabledWidgets |= (1ULL << WIDX_LEVEL);
             }
@@ -857,7 +861,9 @@ static void window_ride_construction_resize(rct_window* w)
             break;
         case TRACK_SLOPE_UP_60:
             disabledWidgets |= (1ULL << WIDX_SLOPE_DOWN_STEEP) | (1ULL << WIDX_SLOPE_DOWN);
-            if (!is_track_enabled(TRACK_SLOPE_LONG) && !is_track_enabled(TRACK_SLOPE_STEEP_LONG))
+            if (!is_track_enabled(TRACK_SLOPE_LONG)
+                && !(is_track_enabled(TRACK_SLOPE_STEEP_LONG)
+                     && !track_piece_direction_is_diagonal(_currentTrackPieceDirection)))
             {
                 disabledWidgets |= (1ULL << WIDX_LEVEL);
             }
@@ -4694,3 +4700,8 @@ void window_ride_construction_keyboard_shortcut_demolish_current()
 
     window_event_mouse_up_call(w, WIDX_DEMOLISH);
 }
+
+static bool track_piece_direction_is_diagonal(const uint8_t direction)
+{
+    return direction >= 4;
+}