diff --git a/spec/core_functions/meta/feature_exists.hrx b/spec/core_functions/meta/feature_exists.hrx
index 92eaadab60..430aedbbc2 100644
--- a/spec/core_functions/meta/feature_exists.hrx
+++ b/spec/core_functions/meta/feature_exists.hrx
@@ -12,6 +12,16 @@ a {
   b: true;
 }
 
+<===> global_variable_shadowing/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(global-variable-shadowing)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> extend_selector_pseudoclass/input.scss
@@ -22,6 +32,16 @@ a {
   b: true;
 }
 
+<===> extend_selector_pseudoclass/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(extend-selector-pseudoclass)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> units_level_3/input.scss
@@ -32,6 +52,16 @@ a {
   b: true;
 }
 
+<===> units_level_3/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(units-level-3)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> at_error/input.scss
@@ -42,6 +72,16 @@ a {
   b: true;
 }
 
+<===> at_error/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(at-error)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> custom_property/input.scss
@@ -52,6 +92,16 @@ a {
   b: true;
 }
 
+<===> custom_property/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(custom-property)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> unknown/input.scss
@@ -62,6 +112,16 @@ a {
   b: false;
 }
 
+<===> unknown/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(unknown)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> dash_sensitive/input.scss
@@ -72,6 +132,16 @@ a {
   b: false;
 }
 
+<===> dash_sensitive/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(at_error)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> quote_insensitive/input.scss
@@ -82,6 +152,16 @@ a {
   b: true;
 }
 
+<===> quote_insensitive/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists("at-error")}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> named/input.scss
@@ -92,12 +172,31 @@ a {
   b: true;
 }
 
+<===> named/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists($feature: at-error)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 <===>
 ================================================================================
 <===> error/type/input.scss
 a {b: feature-exists(1)}
 
 <===> error/type/error
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | a {b: feature-exists(1)}
+  |       ^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:7  root stylesheet
+
 Error: $feature: 1 is not a string.
   ,
 1 | a {b: feature-exists(1)}
diff --git a/spec/core_functions/modules/meta.hrx b/spec/core_functions/modules/meta.hrx
index 5836feaf47..b2861980d1 100644
--- a/spec/core_functions/modules/meta.hrx
+++ b/spec/core_functions/modules/meta.hrx
@@ -18,6 +18,16 @@ a {
   b: true;
 }
 
+<===> feature_exists/warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+2 | a {b: meta.feature-exists(at-error)}
+  |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 2:7  root stylesheet
+
 <===>
 ================================================================================
 <===> variable_exists/input.scss
diff --git a/spec/libsass-closed-issues/issue_702.hrx b/spec/libsass-closed-issues/issue_702.hrx
index 77625a2821..fd036541f9 100644
--- a/spec/libsass-closed-issues/issue_702.hrx
+++ b/spec/libsass-closed-issues/issue_702.hrx
@@ -9,3 +9,13 @@
   content: true;
   content: false;
 }
+
+<===> warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+3 |   content: feature-exists("foo");
+  |            ^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 3:12  root stylesheet
diff --git a/spec/libsass/at-error/feature-test.hrx b/spec/libsass/at-error/feature-test.hrx
index 1d1635f5ec..7f2161bb20 100644
--- a/spec/libsass/at-error/feature-test.hrx
+++ b/spec/libsass/at-error/feature-test.hrx
@@ -9,3 +9,13 @@
 div {
   feature: true;
 }
+
+<===> warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | @if feature-exists(at-error) {
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:5  root stylesheet
diff --git a/spec/libsass/units/feature-test.hrx b/spec/libsass/units/feature-test.hrx
index 6dbf81295e..c08d1b3c88 100644
--- a/spec/libsass/units/feature-test.hrx
+++ b/spec/libsass/units/feature-test.hrx
@@ -9,3 +9,13 @@
 div {
   feature: true;
 }
+
+<===> warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | @if feature-exists(units-level-3) {
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:5  root stylesheet
diff --git a/spec/libsass/variable-scoping/feature-test.hrx b/spec/libsass/variable-scoping/feature-test.hrx
index b387b1af3b..ede9e7b2f1 100644
--- a/spec/libsass/variable-scoping/feature-test.hrx
+++ b/spec/libsass/variable-scoping/feature-test.hrx
@@ -8,3 +8,13 @@
 div {
   feature: true;
 }
+
+<===> warning
+DEPRECATION WARNING: The feature-exists() function is deprecated.
+More info: https://sass-lang.com/d/feature-exists
+
+  ,
+1 | @if feature-exists(global-variable-shadowing) {
+  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+  '
+    input.scss 1:5  root stylesheet