Please could Geany provide a spelling suggestions drop down like auto-complete for spelling errors rather than a mere underline as autocomplete is so much more efficient? Thanks!

Spell checker is a plugin (https://plugins.geany.org/spellcheck.html) so transferred to plugins.
There is already a list of suggestions in the context menu (just right-click on underlined word):

This feature can be activated in the plugin preferences dialog. I don't think it's worth the effort to implement the suggestions as an auto-complete list as most users probably are used to reach the suggestions via a context menu.
Re-open if you heavily disagree :D.
Closed #1081.
as most users probably are used to reach the suggestions via a context menu.
Just to concur, for instance that is how it works for underlined spelling here in GitHub, in Libre Office writer, Xed, Gedit, Vscode as examples.
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