migrate some notes on over here

diff --git a/docs/migration.md b/docs/migration.md
index d6f916ba5a00999061ba74526dc4b4780e301a32..0fa50963816cdb0c9f6c613a102e12f2696ecdcd 100644 (file)
--- a/docs/migration.md
+++ b/docs/migration.md
@@ -141,7 +141,16 @@ New to Bootstrap 4 is the Reboot, a new stylesheet that builds on Normalize with
 
 ### Navbar
 
-- Dropped the `.navbar-form` class entirely. It's no longer necessary.
+The navbar has been entirely rewritten in flexbox with improved support for alignment, responsiveness, and customization.
+
+- Responsive navbar behaviors are now applied to the `.navbar` class via the **required** `.navbar-toggleable-{breakpoint}` where you choose where to collapse the navbar. Previously this was a Less variable modification and required recompiling.
+- `.navbar-default` is now `.navbar-light`, though `.navbar-inverse` remains the same. **One of these is required on each navbar.** However, these classes no longer set `background-color`s; instead they essentiatlly only affect `color`.
+- Navbars now require a background declaration of some kind. Choose from our background utilities (`.bg-*`) or set your own with the light/inverse classes above [for mad customization]({{ site.baseurl }}/components/navbar/#color-schemes).
+- Given flexbox styles, navbars can now use flexbox utilities for easy alignment options.
+- `.navbar-toggle` is now `.navbar-toggler` and has different styles and inner markup (no more three `<span>`s).
+- Dropped the `.navbar-form` class entirely. It's no longer necessary; instead, just use `.form-inline` and apply margin utilities as necessary.
+- Navbars no longer include `margin-bottom` or `border-radius` by default. Use utilities as necessary.
+- All examples featuring navbars have been updated to include new markup.
 
 ### Pagination