diff --git a/doc/lua_api.md b/doc/lua_api.md
index aeb903ae2..57c99ef9d 100644
--- a/doc/lua_api.md
+++ b/doc/lua_api.md
@@ -490,6 +490,11 @@ to let the client generate textures on-the-fly.
 The modifiers are applied directly in sRGB colorspace,
 i.e. without gamma-correction.
 
+### Notes
+
+ * `TEXMOD_UPSCALE`: The texture with the lower resolution will be automatically
+   upscaled to the higher resolution texture.
+
 ### Texture overlaying
 
 Textures can be overlaid by putting a `^` between them.
@@ -503,8 +508,9 @@ Example:
     default_dirt.png^default_grass_side.png
 
 `default_grass_side.png` is overlaid over `default_dirt.png`.
-The texture with the lower resolution will be automatically upscaled to
-the higher resolution texture.
+
+*See notes: `TEXMOD_UPSCALE`*
+
 
 ### Texture grouping
 
@@ -701,6 +707,8 @@ Apply a mask to the base image.
 
 The mask is applied using binary AND.
 
+*See notes: `TEXMOD_UPSCALE`*
+
 #### `[sheet:<w>x<h>:<x>,<y>`
 
 Retrieves a tile at position x, y (in tiles, 0-indexed)
@@ -798,6 +806,8 @@ in GIMP. Overlay is the same as Hard light but with the role of the two
 textures swapped, see the `[hardlight` modifier description for more detail
 about these blend modes.
 
+*See notes: `TEXMOD_UPSCALE`*
+
 #### `[hardlight:<file>`
 
 Applies a Hard light blend with the two textures, like the Hard light layer
@@ -813,6 +823,8 @@ increase contrast without clipping.
 Hard light is the same as Overlay but with the roles of the two textures
 swapped, i.e. `A.png^[hardlight:B.png` is the same as `B.png^[overlay:A.png`
 
+*See notes: `TEXMOD_UPSCALE`*
+
 #### `[png:<base64>`
 
 Embed a base64 encoded PNG image in the texture string.
@@ -831,6 +843,8 @@ In particular consider `minetest.dynamic_add_media` and test whether
 using other texture modifiers could result in a shorter string than
 embedding a whole image, this may vary by use case.
 
+*See notes: `TEXMOD_UPSCALE`*
+
 Hardware coloring
 -----------------
 
diff --git a/games/devtest/mods/testnodes/textures.lua b/games/devtest/mods/testnodes/textures.lua
index 96f291d6a..b95fbd62e 100644
--- a/games/devtest/mods/testnodes/textures.lua
+++ b/games/devtest/mods/testnodes/textures.lua
@@ -52,6 +52,12 @@ minetest.register_node("testnodes:fill_positioning_reference", {
 	groups = {dig_immediate = 3},
 })
 
+minetest.register_node("testnodes:modifier_mask", {
+	description = S("[mask Modifier Test Node"),
+	tiles = {"testnodes_128x128_rgb.png^[mask:testnodes_mask_WRGBKW.png"},
+	groups = {dig_immediate = 3},
+})
+
 -- Node texture transparency test
 
 local alphas = { 64, 128, 191 }
diff --git a/games/devtest/mods/testnodes/textures/testnodes_128x128_rgb.png b/games/devtest/mods/testnodes/textures/testnodes_128x128_rgb.png
new file mode 100644
index 000000000..060d8e67a
Binary files /dev/null and b/games/devtest/mods/testnodes/textures/testnodes_128x128_rgb.png differ
diff --git a/games/devtest/mods/testnodes/textures/testnodes_mask_WRGBKW.png b/games/devtest/mods/testnodes/textures/testnodes_mask_WRGBKW.png
new file mode 100644
index 000000000..03ab71e3f
Binary files /dev/null and b/games/devtest/mods/testnodes/textures/testnodes_mask_WRGBKW.png differ
diff --git a/src/client/imagesource.cpp b/src/client/imagesource.cpp
index bb6668264..195d57a41 100644
--- a/src/client/imagesource.cpp
+++ b/src/client/imagesource.cpp
@@ -1447,6 +1447,8 @@ bool ImageSource::generateImagePart(std::string_view part_of_name,
 
 			video::IImage *img = generateImage(filename, source_image_names);
 			if (img) {
+				upscaleImagesToMatchLargest(baseimg, img);
+
 				apply_mask(img, baseimg, v2s32(0, 0), v2s32(0, 0),
 						img->getDimension());
 				img->drop();