[gimp-web] Add JPEG-XL exporting options screenshot

[Alexandre Prokoudine <aprokoudine src gnome org>]

commit 0f434c2aaf0ec251980910d044c32ac89aede4bd
Author: Alexandre Prokoudine <alexandre prokoudine gmail com>
Date:   Mon Oct 18 17:47:01 2021 +0300

    Add JPEG-XL exporting options screenshot

 .../gimp-2-99-8-jxl-exporting.jpg                      | Bin 0 -> 228469 bytes
 .../news/2021/2021-10_GIMP-2.99.8_Released/index.md    |   7 +++++++
 2 files changed, 7 insertions(+)
---
diff --git a/content/news/2021/2021-10_GIMP-2.99.8_Released/gimp-2-99-8-jxl-exporting.jpg 
b/content/news/2021/2021-10_GIMP-2.99.8_Released/gimp-2-99-8-jxl-exporting.jpg
new file mode 100644
index 00000000..edcf3513
Binary files /dev/null and b/content/news/2021/2021-10_GIMP-2.99.8_Released/gimp-2-99-8-jxl-exporting.jpg 
differ
diff --git a/content/news/2021/2021-10_GIMP-2.99.8_Released/index.md 
b/content/news/2021/2021-10_GIMP-2.99.8_Released/index.md
index 75c74e57..249004c9 100644
--- a/content/news/2021/2021-10_GIMP-2.99.8_Released/index.md
+++ b/content/news/2021/2021-10_GIMP-2.99.8_Released/index.md
@@ -111,6 +111,13 @@ GIMP can now load and export JPEG-XL files (`.jxl`) in grayscale and
 RGB, with color profiles support. Our exporting code also provides
 a "*lossless*" option and several "*speed*" encoding values.
 
+<figure>
+<img src="{attach}gimp-2-99-8-jxl-exporting.jpg" alt="JPEG-XL exporting options — GIMP 2.99.8"/>
+<figcaption>
+<em>JPEG-XL exporting options — GIMP 2.99.8</em>
+</figcaption>
+</figure>
+
 This plug-in is different from the [third-party 
plug-in](https://github.com/libjxl/libjxl/tree/main/plugins/gimp) that is part of the `libjxl` library
 that we use too. It supports GIMP 3 plugin API, reads greyscale images
 as greyscale, is written in C rather than C++, and exposes several presets