DOC-3131: Add changelog.

Author: kemister85

modules/ROOT/pages/changelog.adoc

@@ -4,6 +4,40 @@
 
 NOTE: This is the {productname} Community version changelog. For information about the latest {cloudname} or {enterpriseversion} Release, see: xref:release-notes.adoc[{productname} Release Notes].
 
+== xref:7.8.0-release-notes.adoc[7.8.0 - 2025-04-9]
+
+=== Added
+* New subtoolbar support for context toolbars.
+// #TINY-11748
+* New `extended_mathml_attributes` and `extended_mathml_elements` options.
+// #TINY-11756
+* New `onboarding` option.
+// #TINY-11931
+
+=== Improved
+* Dialog menu dropdowns now close when a dialog is moved.
+// #TINY-11368
+* Focus outline was misaligned with comment card border on saving an edit.
+// #TINY-11329
+* The `editor.selection.scrollIntoView()` method now pads the target scroll area with a small margin, ensuring content doesn't sit at the very edge of the viewport.
+// #TINY-11786
+
+=== Changed
+* Changed promotional text and link.
+// #TINY-11905
+
+=== Fixed
+* Setting editor height to a `pt` or `em` value was ignoring min/max height settings.
+// #TINY-11108
+* Exception when pressing tab in the last cell of a non-editable table.
+// #TINY-11797
+* Exception was thrown when trying to use context form API after component was detached.
+// #TINY-11781
+* Deleting an empty block within <li> would move cursor at the end of the <li>.
+// #TINY-11763
+* Deleting an empty block that is between two lists would throw an error when all of the elements were nested inside the same <li>.
+// #TINY-11763
+
 == xref:7.7.2-release-notes.adoc[7.7.2 - 2025-03-19]
 
 === Fixed