layout2020: backdrop filter creates a stacking context

Signed-off-by: Josh <36625023+JoshuaBrest@users.noreply.github.com>

Author: JoshuaBrest

Cargo.lock

@@ -115,25 +115,25 @@ rustls-pemfile = "2.0"
 rustls-pki-types = "1.11"
 script_layout_interface = { path = "components/shared/script_layout" }
 script_traits = { path = "components/shared/script" }
-selectors = { git = "https://github.com/servo/stylo", branch = "2025-02-03" }
+selectors = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter" }
 serde = "1.0.217"
 serde_bytes = "0.11"
 serde_json = "1.0"
 servo-media = { git = "https://github.com/servo/media" }
 servo-media-dummy = { git = "https://github.com/servo/media" }
 servo-media-gstreamer = { git = "https://github.com/servo/media" }
-servo_arc = { git = "https://github.com/servo/stylo", branch = "2025-02-03", features = ["servo"] }
-servo_atoms = { git = "https://github.com/servo/stylo", branch = "2025-02-03" }
+servo_arc = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter", features = ["servo"] }
+servo_atoms = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter" }
 smallbitvec = "2.5.3"
 smallvec = "1.13"
 static_assertions = "1.1"
 string_cache = "0.8"
 string_cache_codegen = "0.5"
-style = { git = "https://github.com/servo/stylo", branch = "2025-02-03", features = ["servo"] }
-style_config = { git = "https://github.com/servo/stylo", branch = "2025-02-03" }
-style_dom = { git = "https://github.com/servo/stylo", package = "dom", branch = "2025-02-03" }
-style_malloc_size_of = { package = "malloc_size_of", git = "https://github.com/servo/stylo", branch = "2025-02-03", features = ["servo"] }
-style_traits = { git = "https://github.com/servo/stylo", branch = "2025-02-03", features = ["servo"] }
+style = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter", features = ["servo"] }
+style_config = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter" }
+style_dom = { git = "https://github.com/JoshuaBrest/stylo", package = "dom", branch = "stacking-context-backdrop-filter" }
+style_malloc_size_of = { package = "malloc_size_of", git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter", features = ["servo"] }
+style_traits = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter", features = ["servo"] }
 surfman = { git = "https://github.com/servo/surfman", rev = "a8079ee2708619926d07c5a2088b8c9af99abdb3", features = ["chains"] }
 syn = { version = "2", default-features = false, features = ["clone-impls", "derive", "parsing"] }
 synstructure = "0.13"
@@ -142,7 +142,7 @@ thin-vec = "0.2.13"
 tikv-jemalloc-sys = "0.6.0"
 tikv-jemallocator = "0.6.0"
 time = { package = "time", version = "0.3", features = ["large-dates", "local-offset", "serde"] }
-to_shmem = { git = "https://github.com/servo/stylo", branch = "2025-02-03" }
+to_shmem = { git = "https://github.com/JoshuaBrest/stylo", branch = "stacking-context-backdrop-filter" }
 tokio = "1"
 tokio-rustls = { version = "0.26", default-features = false, features = ["logging"] }
 tower-service = "0.3"
@@ -210,7 +210,7 @@ codegen-units = 1
 #
 # Or for Stylo:
 #
-# [patch."https://github.com/servo/stylo"]
+# [patch."https://github.com/JoshuaBrest/stylo"]
 # selectors = { path = "../stylo/selectors" }
 # servo_arc = { path = "../stylo/servo_arc" }
 # servo_atoms = { path = "../stylo/atoms" }

Cargo.toml

@@ -589,6 +589,7 @@ impl ComputedValuesExt for ComputedValues {
     /// Returns true if this fragment establishes a new stacking context and false otherwise.
     fn establishes_stacking_context(&self, fragment_flags: FragmentFlags) -> bool {
         let effects = self.get_effects();
+
         if effects.opacity != 1.0 {
             return true;
         }
@@ -601,7 +602,11 @@ impl ComputedValuesExt for ComputedValues {
             return true;
         }
 
-        if !self.get_effects().filter.0.is_empty() {
+        if !effects.filter.0.is_empty() {
+            return true;
+        }
+
+        if !effects.backdrop_filter.0.is_empty() {
             return true;
         }
 
@@ -671,7 +676,10 @@ impl ComputedValuesExt for ComputedValues {
             return true;
         }
 
-        if !self.get_effects().filter.0.is_empty() {
+        // FIXME(#35391): `filter` and `backdrop-filter` shouldn't establish
+        // a containing block when applied to the document root element.
+        let effects = self.get_effects();
+        if !effects.filter.0.is_empty() || !effects.backdrop_filter.0.is_empty() {
             return true;
         }