diff --git a/files/en-us/web/mathml/global_attributes/displaystyle/index.md b/files/en-us/web/mathml/global_attributes/displaystyle/index.md
index 56ed37d3f3f299c..a15e3e94f1c0d3d 100644
--- a/files/en-us/web/mathml/global_attributes/displaystyle/index.md
+++ b/files/en-us/web/mathml/global_attributes/displaystyle/index.md
@@ -42,10 +42,6 @@ In this example, an [munder](/en-US/docs/Web/MathML/Element/munder) element is u
 - `false`
    -: Sets the display style to `compact`.
 
-## Notes on MathML versions
-
-- MathML Core relies on `math-style` to implement the `displaystyle` attribute, but implementations of older MathML versions may follow a different approach to implement similar behavior.
-
 ## Specifications
 
 {{Specifications}}
diff --git a/files/en-us/web/mathml/global_attributes/mathsize/index.md b/files/en-us/web/mathml/global_attributes/mathsize/index.md
index ab7ba019e28aa2d..10c1cd5bc1cb8de 100644
--- a/files/en-us/web/mathml/global_attributes/mathsize/index.md
+++ b/files/en-us/web/mathml/global_attributes/mathsize/index.md
@@ -32,8 +32,6 @@ The **`mathsize`** [global attribute](/en-US/docs/Web/MathML/Global_attributes)
 - {{cssxref("<percentage>")}}
   - : A positive {{cssxref("<percentage>")}} value, relative to the parent element's font size.
 
-## Notes on MathML versions
-
 ## Specifications
 
 {{Specifications}}
diff --git a/files/en-us/web/mathml/global_attributes/mathvariant/index.md b/files/en-us/web/mathml/global_attributes/mathvariant/index.md
index 6c461b64fcbece0..52ba2504ba65783 100644
--- a/files/en-us/web/mathml/global_attributes/mathvariant/index.md
+++ b/files/en-us/web/mathml/global_attributes/mathvariant/index.md
@@ -92,12 +92,6 @@ which are by convention italic, no special classes are used by default.
 - `stretched`
    -: Try and use stretched characters e.g. "𞹢".
 
-## Notes on MathML versions
-
-- `mathvariant` values other than `normal` were designed for backward compatibility. Authors are encouraged to instead directly use the corresponding Unicode characters from the [Mathematical Alphanumeric Symbols](https://en.wikipedia.org/wiki/Mathematical_Alphanumeric_Symbols).
-
-- MathML Core relies on `text-transform` to implement the `mathvariant` attribute, but implementations of older MathML versions may follow a different approach to implement similar behavior.
-
 ## Specifications
 
 {{Specifications}}
@@ -105,7 +99,6 @@ which are by convention italic, no special classes are used by default.
 ## Browser compatibility
 
 {{Compat}}
-On Firefox, some `mathvariant` values are only implemented starting with Firefox 28 and require appropriate [math fonts](/en-US/docs/Web/MathML/Fonts).
 
 ## See also
 
diff --git a/files/en-us/web/mathml/global_attributes/scriptlevel/index.md b/files/en-us/web/mathml/global_attributes/scriptlevel/index.md
index a8d7a4fafc847bc..ab58d148b671ff7 100644
--- a/files/en-us/web/mathml/global_attributes/scriptlevel/index.md
+++ b/files/en-us/web/mathml/global_attributes/scriptlevel/index.md
@@ -52,10 +52,6 @@ If `<U>` is an unsigned [integer](/en-US/docs/Web/CSS/integer) (i.e. with prefix
       -: Sets the `math-depth` to value `add(-<U>)`. This will scale up
         `font-size` on the element `<U>` times.
 
-## Notes on MathML versions
-
-- MathML Core relies on `math-depth` to implement the `scriptlevel` attribute, but implementations of older MathML versions may follow a different approach to implement similar side-effect on the `font-size` within mathematical formulas.
-
 ## Specifications
 
 {{Specifications}}