[gimp] NEWS: update.

[Jehan <jehanp src gnome org>]

commit 2c3e65a6b6aed39ce4db5a5b2e4f6e25e7f583af
Author: Jehan <jehan girinstud io>
Date:   Sat Sep 10 23:45:08 2022 +0200

    NEWS: update.

 NEWS | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
---
diff --git a/NEWS b/NEWS
index d91947843e..b1796e2c38 100644
--- a/NEWS
+++ b/NEWS
@@ -9,9 +9,30 @@ This is the unstable branch of GIMP.
 Overview of Changes from GIMP 2.99.12 to GIMP 2.99.14
 =====================================================
 
+Core:
+
+  - The download button in About dialog when a new version is available
+    will now show the development download page when running unstable
+    branch code.
+  - The update check on macOS now uses native HTTPS-able API, so that we
+    don't have to wait for GIO to have HTTPS modules for macOS.
+
+Plug-ins:
+
+  - PDF:
+    * Export code was ported to GimpProcedureDialog.
+    * New "root-layers-only" argument to "file-pdf-save", which comes
+      with a checkbox in the export dialog to allow exporting as pages
+      the root layers only. The main usage is to organize your pages'
+      contents in layer groups.
+
 Build:
 
   - meson requirement bump to meson 0.56.0.
+  - Many fixes to the meson build scripts, making it closer to be our
+    official build for GIMP 3.0.
+  - The CI now generates a tarball containing the GIMP references,
+    generated by gi-docgen and g-ir-doc.
 
 
 Overview of Changes from GIMP 2.99.10 to GIMP 2.99.12