Editing a shadow tiddler creates an “ordinary” tiddler with the same name which overrides the original shadow definition, but does not overwrite or remove that definition. To restore the original shadow definition, you simply delete (or rename) the overriding ordinary tiddler, which allows the original version to “re-emerge from the shadows” (hence the name!)
The “about to edit a ShadowTiddler” warning is generic when ANY shadow tiddler is about to be modified. If you subsequently upgrade the TWCore (i.e., using the TiddlyWiki Upgrader), ALL shadow tiddlers will still be upgraded at that time. However, any shadows that you have edited are still overridden by your previous changes, so any improvements to those particular shadow tiddlers won’t be applied.
For many shadow tiddlers, this is not a problem, unless you have changed a shadow tiddler that contains javascript code (which also requires a save-and-reload before those changes are applied). As a general rule you should always save a backup copy of your TiddlyWiki before making any changes, so if something does go wrong, you can easily revert to your most recent working version.
Small changes to “ui” shadow tiddlers are a normal part of customizing your TiddlyWiki to suit your needs. The change to $:/core/ui/ViewTemplate/tags
that I suggested is actually VERY safe, as it extends the default TWCore behavior, but doesn’t alter that default behavior if the $:/config/TagDisplayOrder
tiddler is empty or not present.
Go ahead and give it a try.
-e