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+++ b/book/intro.md
@@ -1,3 +1,28 @@
 # Home
 
 This is an introduction to Git, VS Code and Jupyter Books for teachers of MUDE. Topics that are covered include: installing Git and VS Code, setting up SSH-keys for GitLab, the basic structure of Jupyter Books and basic Git workflows. 
+
+## List of things to add
+
+Robert created this list to keep track of things that should be in our manual. Especially the small problems we have run into in MUDE and other projects.
+
+- use the right HTML tags for images (described {ref}`here <image-tag-example>`)
+- watch out for `png` versus `PNG`
+- trick for creating download link for PDFs (see Archive weekly summary pages); requires an `eval-rst` admonition, which can't be placed inside some objects (maybe someone can test this, and see if an inline option is available)
+
+(image-tag-example)=
+### Example of image tag
+
+This was found in the MUDE Archive, [Issue 29](https://gitlab.tudelft.nl/mude/archive-2022/-/issues/29).
+
+It looks like the `figure` tag
+```
+<figure>
+  <IMG SRC='...'>
+</figure>
+```
+is not supported. but the `img` tag is:
+```
+<img src="...">
+```
+see examples [here](https://jupyterbook.org/en/stable/content/figures.html) (no `figure` tag mentioned for HTML, only Markdown)