Added note on Confluence and on Markdown.

applications/lofar2/doc/prestudy/desp_howtools_erko.txt

@@ -302,6 +302,16 @@ Note:
 - space tools menu, content tools, custom export to PDF --> to export multiple
   pages to PDF and to preserve th ASTRON logo in the export
 
+I notice that in a Confluence document from Gijs that if I try to do a comment
+on a text that contains capital charcters it fails, and if I try to place the
+comment on text with only small characters it accepts the comment. Strange,
+but for me it is an ok workaround.
+
+
+Sometimes in a Confluence document in edit mode all Figures have collapsed into
+small narrow icons. I can recover them by selecting the Figure icon and then
+choosing the expand button  in the bar on top or below the Figure. Weird, but
+for me it is an ok workaround,
 
 *******************************************************************************
 * Polarion:
@@ -325,6 +335,12 @@ Note:
 * Markdown
 *******************************************************************************
 
+Use e.g. Linux 'retext' as markdown editor and previewer. Markdown is not well 
+defined, so it is not always sure that the text will appear as expected in
+each viewer. For example retext and gitlab viewer differ. Therefore it is
+important to keep the markdown simple and to accept that readable text is good
+enough, rather than to strive for a specific layout.
+
 Text will wrap.
 
 Backslash is escape chararcter.