diff --git a/Tests/LibGfx/TestImageDecoder.cpp b/Tests/LibGfx/TestImageDecoder.cpp
index ced7b2a351..6597fc3d91 100644
--- a/Tests/LibGfx/TestImageDecoder.cpp
+++ b/Tests/LibGfx/TestImageDecoder.cpp
@@ -31,7 +31,7 @@
 TEST_CASE(test_bmp)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("rgba32-1.bmp"sv)));
-    EXPECT(MUST(Gfx::BMPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::BMPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::BMPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -46,7 +46,7 @@ TEST_CASE(test_bmp)
 TEST_CASE(test_gif)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("download-animation.gif"sv)));
-    EXPECT(MUST(Gfx::GIFImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::GIFImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::GIFImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -61,7 +61,7 @@ TEST_CASE(test_gif)
 TEST_CASE(test_not_ico)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("buggie.png"sv)));
-    EXPECT(!MUST(Gfx::ICOImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(!Gfx::ICOImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::ICOImageDecoderPlugin::create(file->bytes()));
     EXPECT(!plugin_decoder->initialize());
 
@@ -75,7 +75,7 @@ TEST_CASE(test_not_ico)
 TEST_CASE(test_bmp_embedded_in_ico)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("serenity.ico"sv)));
-    EXPECT(MUST(Gfx::ICOImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::ICOImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::ICOImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -89,7 +89,7 @@ TEST_CASE(test_bmp_embedded_in_ico)
 TEST_CASE(test_jpg)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("rgb24.jpg"sv)));
-    EXPECT(MUST(Gfx::JPEGImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::JPEGImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::JPEGImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -104,7 +104,7 @@ TEST_CASE(test_jpg)
 TEST_CASE(test_pbm)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("buggie-raw.pbm"sv)));
-    EXPECT(MUST(Gfx::PBMImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::PBMImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::PBMImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -119,7 +119,7 @@ TEST_CASE(test_pbm)
 TEST_CASE(test_pgm)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("buggie-raw.pgm"sv)));
-    EXPECT(MUST(Gfx::PGMImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::PGMImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::PGMImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -134,7 +134,7 @@ TEST_CASE(test_pgm)
 TEST_CASE(test_png)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("buggie.png"sv)));
-    EXPECT(MUST(Gfx::PNGImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::PNGImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::PNGImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -149,7 +149,7 @@ TEST_CASE(test_png)
 TEST_CASE(test_ppm)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("buggie-raw.ppm"sv)));
-    EXPECT(MUST(Gfx::PPMImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::PPMImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::PPMImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -224,7 +224,7 @@ TEST_CASE(test_targa_top_left_compressed)
 TEST_CASE(test_webp_simple_lossy)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("simple-vp8.webp"sv)));
-    EXPECT(MUST(Gfx::WebPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::WebPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::WebPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -238,7 +238,7 @@ TEST_CASE(test_webp_simple_lossy)
 TEST_CASE(test_webp_simple_lossless)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("simple-vp8l.webp"sv)));
-    EXPECT(MUST(Gfx::WebPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::WebPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::WebPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -252,7 +252,7 @@ TEST_CASE(test_webp_simple_lossless)
 TEST_CASE(test_webp_extended_lossy)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("extended-lossy.webp"sv)));
-    EXPECT(MUST(Gfx::WebPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::WebPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::WebPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -266,7 +266,7 @@ TEST_CASE(test_webp_extended_lossy)
 TEST_CASE(test_webp_extended_lossless)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("extended-lossless.webp"sv)));
-    EXPECT(MUST(Gfx::WebPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::WebPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::WebPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
@@ -280,7 +280,7 @@ TEST_CASE(test_webp_extended_lossless)
 TEST_CASE(test_webp_extended_lossless_animated)
 {
     auto file = MUST(Core::MappedFile::map(TEST_INPUT("extended-lossless-animated.webp"sv)));
-    EXPECT(MUST(Gfx::WebPImageDecoderPlugin::sniff(file->bytes())));
+    EXPECT(Gfx::WebPImageDecoderPlugin::sniff(file->bytes()));
     auto plugin_decoder = MUST(Gfx::WebPImageDecoderPlugin::create(file->bytes()));
     EXPECT(plugin_decoder->initialize());
 
diff --git a/Userland/Libraries/LibGUI/FileIconProvider.cpp b/Userland/Libraries/LibGUI/FileIconProvider.cpp
index d0f603ac75..0b58a83b13 100644
--- a/Userland/Libraries/LibGUI/FileIconProvider.cpp
+++ b/Userland/Libraries/LibGUI/FileIconProvider.cpp
@@ -210,7 +210,7 @@ Icon FileIconProvider::icon_for_executable(DeprecatedString const& path)
             bitmap = s_executable_icon.bitmap_for_size(icon_section.image_size);
         } else {
             // FIXME: Use the ImageDecoder service.
-            if (Gfx::PNGImageDecoderPlugin::sniff({ section->raw_data(), section->size() }).release_value_but_fixme_should_propagate_errors()) {
+            if (Gfx::PNGImageDecoderPlugin::sniff({ section->raw_data(), section->size() })) {
                 auto png_decoder = Gfx::PNGImageDecoderPlugin::create({ section->raw_data(), section->size() }).release_value_but_fixme_should_propagate_errors();
                 if (png_decoder->initialize()) {
                     auto frame_or_error = png_decoder->frame(0);
diff --git a/Userland/Libraries/LibGfx/BMPLoader.cpp b/Userland/Libraries/LibGfx/BMPLoader.cpp
index ba2d4cd444..7abfffad81 100644
--- a/Userland/Libraries/LibGfx/BMPLoader.cpp
+++ b/Userland/Libraries/LibGfx/BMPLoader.cpp
@@ -1505,7 +1505,7 @@ bool BMPImageDecoderPlugin::initialize()
     return !decode_bmp_header(*m_context).is_error();
 }
 
-ErrorOr<bool> BMPImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool BMPImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     BMPLoadingContext context;
     context.file_bytes = data.data();
diff --git a/Userland/Libraries/LibGfx/BMPLoader.h b/Userland/Libraries/LibGfx/BMPLoader.h
index 0880cf9112..6430d66f94 100644
--- a/Userland/Libraries/LibGfx/BMPLoader.h
+++ b/Userland/Libraries/LibGfx/BMPLoader.h
@@ -16,7 +16,7 @@ class ICOImageDecoderPlugin;
 
 class BMPImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<BMPImageDecoderPlugin>> create_as_included_in_ico(Badge<ICOImageDecoderPlugin>, ReadonlyBytes);
 
diff --git a/Userland/Libraries/LibGfx/DDSLoader.cpp b/Userland/Libraries/LibGfx/DDSLoader.cpp
index cd52d8d615..f2775dbfee 100644
--- a/Userland/Libraries/LibGfx/DDSLoader.cpp
+++ b/Userland/Libraries/LibGfx/DDSLoader.cpp
@@ -656,7 +656,7 @@ bool DDSImageDecoderPlugin::initialize()
         && m_context->data[3] == 0x20;
 }
 
-ErrorOr<bool> DDSImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool DDSImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     // The header is always at least 128 bytes, so if the file is smaller, it can't be a DDS.
     return data.size() > 128
diff --git a/Userland/Libraries/LibGfx/DDSLoader.h b/Userland/Libraries/LibGfx/DDSLoader.h
index 21f79bbec2..bc9c6e250f 100644
--- a/Userland/Libraries/LibGfx/DDSLoader.h
+++ b/Userland/Libraries/LibGfx/DDSLoader.h
@@ -235,7 +235,7 @@ struct DDSLoadingContext;
 
 class DDSImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~DDSImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibGfx/GIFLoader.cpp b/Userland/Libraries/LibGfx/GIFLoader.cpp
index d952d05ed7..215d5d1d3d 100644
--- a/Userland/Libraries/LibGfx/GIFLoader.cpp
+++ b/Userland/Libraries/LibGfx/GIFLoader.cpp
@@ -569,7 +569,7 @@ bool GIFImageDecoderPlugin::initialize()
     return !decode_gif_header(stream).is_error();
 }
 
-ErrorOr<bool> GIFImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool GIFImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     FixedMemoryStream stream { data };
     return !decode_gif_header(stream).is_error();
diff --git a/Userland/Libraries/LibGfx/GIFLoader.h b/Userland/Libraries/LibGfx/GIFLoader.h
index 0492945f20..deaa011bea 100644
--- a/Userland/Libraries/LibGfx/GIFLoader.h
+++ b/Userland/Libraries/LibGfx/GIFLoader.h
@@ -15,7 +15,7 @@ struct GIFLoadingContext;
 
 class GIFImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~GIFImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibGfx/ICOLoader.cpp b/Userland/Libraries/LibGfx/ICOLoader.cpp
index fb6b25baa2..d26a693c2a 100644
--- a/Userland/Libraries/LibGfx/ICOLoader.cpp
+++ b/Userland/Libraries/LibGfx/ICOLoader.cpp
@@ -149,7 +149,7 @@ ErrorOr<void> ICOImageDecoderPlugin::load_ico_bitmap(ICOLoadingContext& context,
         return Error::from_string_literal("Index out of bounds");
 
     ICOImageDescriptor& desc = context.images[real_index];
-    if (TRY(PNGImageDecoderPlugin::sniff({ context.data + desc.offset, desc.size }))) {
+    if (PNGImageDecoderPlugin::sniff({ context.data + desc.offset, desc.size })) {
         auto png_decoder = TRY(PNGImageDecoderPlugin::create({ context.data + desc.offset, desc.size }));
         if (png_decoder->initialize()) {
             auto decoded_png_frame = TRY(png_decoder->frame(0));
@@ -181,7 +181,7 @@ ErrorOr<void> ICOImageDecoderPlugin::load_ico_bitmap(ICOLoadingContext& context,
     }
 }
 
-ErrorOr<bool> ICOImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool ICOImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     FixedMemoryStream stream { data };
     return !decode_ico_header(stream).is_error();
diff --git a/Userland/Libraries/LibGfx/ICOLoader.h b/Userland/Libraries/LibGfx/ICOLoader.h
index 8d7f1713f1..eecd7d396b 100644
--- a/Userland/Libraries/LibGfx/ICOLoader.h
+++ b/Userland/Libraries/LibGfx/ICOLoader.h
@@ -14,7 +14,7 @@ struct ICOLoadingContext;
 
 class ICOImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~ICOImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibGfx/ImageDecoder.cpp b/Userland/Libraries/LibGfx/ImageDecoder.cpp
index 3a404d44d3..19c96d9f83 100644
--- a/Userland/Libraries/LibGfx/ImageDecoder.cpp
+++ b/Userland/Libraries/LibGfx/ImageDecoder.cpp
@@ -22,7 +22,7 @@
 namespace Gfx {
 
 struct ImagePluginInitializer {
-    ErrorOr<bool> (*sniff)(ReadonlyBytes) = nullptr;
+    bool (*sniff)(ReadonlyBytes) = nullptr;
     ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> (*create)(ReadonlyBytes) = nullptr;
 };
 
@@ -53,7 +53,7 @@ static constexpr ImagePluginWithMIMETypeInitializer s_initializers_with_mime_typ
 static OwnPtr<ImageDecoderPlugin> probe_and_sniff_for_appropriate_plugin(ReadonlyBytes bytes)
 {
     for (auto& plugin : s_initializers) {
-        auto sniff_result = plugin.sniff(bytes).release_value_but_fixme_should_propagate_errors();
+        auto sniff_result = plugin.sniff(bytes);
         if (!sniff_result)
             continue;
         auto plugin_decoder = plugin.create(bytes).release_value_but_fixme_should_propagate_errors();
diff --git a/Userland/Libraries/LibGfx/JPEGLoader.cpp b/Userland/Libraries/LibGfx/JPEGLoader.cpp
index 74ff397d13..14084ab5d8 100644
--- a/Userland/Libraries/LibGfx/JPEGLoader.cpp
+++ b/Userland/Libraries/LibGfx/JPEGLoader.cpp
@@ -1363,7 +1363,7 @@ bool JPEGImageDecoderPlugin::initialize()
     return true;
 }
 
-ErrorOr<bool> JPEGImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool JPEGImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     return data.size() > 3
         && data.data()[0] == 0xFF
diff --git a/Userland/Libraries/LibGfx/JPEGLoader.h b/Userland/Libraries/LibGfx/JPEGLoader.h
index 146d51e52e..fd2c30ce5d 100644
--- a/Userland/Libraries/LibGfx/JPEGLoader.h
+++ b/Userland/Libraries/LibGfx/JPEGLoader.h
@@ -16,7 +16,7 @@ struct JPEGLoadingContext;
 
 class JPEGImageDecoderPlugin : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~JPEGImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibGfx/PNGLoader.cpp b/Userland/Libraries/LibGfx/PNGLoader.cpp
index 2578eae7ef..26a00a5908 100644
--- a/Userland/Libraries/LibGfx/PNGLoader.cpp
+++ b/Userland/Libraries/LibGfx/PNGLoader.cpp
@@ -1034,7 +1034,7 @@ bool PNGImageDecoderPlugin::initialize()
     return decode_png_header(*m_context);
 }
 
-ErrorOr<bool> PNGImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool PNGImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     PNGLoadingContext context;
     context.data = data.data();
diff --git a/Userland/Libraries/LibGfx/PNGLoader.h b/Userland/Libraries/LibGfx/PNGLoader.h
index 5d04e6a951..80abda9daf 100644
--- a/Userland/Libraries/LibGfx/PNGLoader.h
+++ b/Userland/Libraries/LibGfx/PNGLoader.h
@@ -14,7 +14,7 @@ struct PNGLoadingContext;
 
 class PNGImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~PNGImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibGfx/PortableImageMapLoader.h b/Userland/Libraries/LibGfx/PortableImageMapLoader.h
index 105accc6b2..e6be567dac 100644
--- a/Userland/Libraries/LibGfx/PortableImageMapLoader.h
+++ b/Userland/Libraries/LibGfx/PortableImageMapLoader.h
@@ -49,7 +49,7 @@ struct PortableImageMapLoadingContext {
 template<typename TContext>
 class PortableImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     PortableImageDecoderPlugin(u8 const*, size_t);
@@ -133,7 +133,7 @@ ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> PortableImageDecoderPlugin<TContext>:
 }
 
 template<typename TContext>
-ErrorOr<bool> PortableImageDecoderPlugin<TContext>::sniff(ReadonlyBytes data)
+bool PortableImageDecoderPlugin<TContext>::sniff(ReadonlyBytes data)
 {
     using Context = TContext;
     if (data.size() < 2)
diff --git a/Userland/Libraries/LibGfx/QOILoader.cpp b/Userland/Libraries/LibGfx/QOILoader.cpp
index bddf442cd3..ad6a20c78b 100644
--- a/Userland/Libraries/LibGfx/QOILoader.cpp
+++ b/Userland/Libraries/LibGfx/QOILoader.cpp
@@ -200,7 +200,7 @@ bool QOIImageDecoderPlugin::initialize()
     return !decode_header_and_update_context(*m_context->stream).is_error();
 }
 
-ErrorOr<bool> QOIImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool QOIImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     FixedMemoryStream stream { { data.data(), data.size() } };
     return !decode_qoi_header(stream).is_error();
diff --git a/Userland/Libraries/LibGfx/QOILoader.h b/Userland/Libraries/LibGfx/QOILoader.h
index e6555bdfe8..65fa373864 100644
--- a/Userland/Libraries/LibGfx/QOILoader.h
+++ b/Userland/Libraries/LibGfx/QOILoader.h
@@ -38,7 +38,7 @@ struct QOILoadingContext {
 
 class QOIImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~QOIImageDecoderPlugin() override = default;
diff --git a/Userland/Libraries/LibGfx/WebPLoader.cpp b/Userland/Libraries/LibGfx/WebPLoader.cpp
index c1ed838fa0..d7a288d2fd 100644
--- a/Userland/Libraries/LibGfx/WebPLoader.cpp
+++ b/Userland/Libraries/LibGfx/WebPLoader.cpp
@@ -522,7 +522,7 @@ bool WebPImageDecoderPlugin::initialize()
     return !decode_webp_header(*m_context).is_error();
 }
 
-ErrorOr<bool> WebPImageDecoderPlugin::sniff(ReadonlyBytes data)
+bool WebPImageDecoderPlugin::sniff(ReadonlyBytes data)
 {
     WebPLoadingContext context;
     context.data = data;
diff --git a/Userland/Libraries/LibGfx/WebPLoader.h b/Userland/Libraries/LibGfx/WebPLoader.h
index 8352093f1a..ddc82bd0f8 100644
--- a/Userland/Libraries/LibGfx/WebPLoader.h
+++ b/Userland/Libraries/LibGfx/WebPLoader.h
@@ -14,7 +14,7 @@ struct WebPLoadingContext;
 
 class WebPImageDecoderPlugin final : public ImageDecoderPlugin {
 public:
-    static ErrorOr<bool> sniff(ReadonlyBytes);
+    static bool sniff(ReadonlyBytes);
     static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
 
     virtual ~WebPImageDecoderPlugin() override;
diff --git a/Userland/Libraries/LibPDF/Filter.cpp b/Userland/Libraries/LibPDF/Filter.cpp
index b250101dd1..051fd445e7 100644
--- a/Userland/Libraries/LibPDF/Filter.cpp
+++ b/Userland/Libraries/LibPDF/Filter.cpp
@@ -269,7 +269,7 @@ ErrorOr<ByteBuffer> Filter::decode_jbig2(ReadonlyBytes)
 
 ErrorOr<ByteBuffer> Filter::decode_dct(ReadonlyBytes bytes)
 {
-    if (Gfx::JPEGImageDecoderPlugin::sniff({ bytes.data(), bytes.size() }).release_value_but_fixme_should_propagate_errors()) {
+    if (Gfx::JPEGImageDecoderPlugin::sniff({ bytes.data(), bytes.size() })) {
         auto decoder = Gfx::JPEGImageDecoderPlugin::create({ bytes.data(), bytes.size() }).release_value_but_fixme_should_propagate_errors();
         if (decoder->initialize()) {
             auto frame = TRY(decoder->frame(0));
diff --git a/Userland/Services/SpiceAgent/SpiceAgent.cpp b/Userland/Services/SpiceAgent/SpiceAgent.cpp
index 417962901a..35869eb9f3 100644
--- a/Userland/Services/SpiceAgent/SpiceAgent.cpp
+++ b/Userland/Services/SpiceAgent/SpiceAgent.cpp
@@ -142,19 +142,19 @@ void SpiceAgent::on_message_received()
         } else {
             ErrorOr<Gfx::ImageFrameDescriptor> frame_or_error = Gfx::ImageFrameDescriptor {};
             if (type == ClipboardType::PNG) {
-                if (Gfx::PNGImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors()) {
+                if (Gfx::PNGImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() })) {
                     auto png_decoder = Gfx::PNGImageDecoderPlugin::create({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors();
                     if (png_decoder->initialize())
                         frame_or_error = png_decoder->frame(0);
                 }
             } else if (type == ClipboardType::BMP) {
-                if (Gfx::BMPImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors()) {
+                if (Gfx::BMPImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() })) {
                     auto bmp_decoder = Gfx::BMPImageDecoderPlugin::create({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors();
                     if (bmp_decoder->initialize())
                         frame_or_error = bmp_decoder->frame(0);
                 }
             } else if (type == ClipboardType::JPEG) {
-                if (Gfx::JPEGImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors()) {
+                if (Gfx::JPEGImageDecoderPlugin::sniff({ data_buffer.data(), data_buffer.size() })) {
                     auto jpeg_decoder = Gfx::JPEGImageDecoderPlugin::create({ data_buffer.data(), data_buffer.size() }).release_value_but_fixme_should_propagate_errors();
                     if (jpeg_decoder->initialize())
                         frame_or_error = jpeg_decoder->frame(0);