The code tried hard to ignore garbage URLs, as Qt is quite lenient, e.g. QUrl("Garbage Url") is still valid.
There is no way to change the strictness of a QUrl after creation, so the code would enforce it by doing QUrl strictUrl(inputUrl.toString(), QUrl::StrictMode).
However, toString() defaults to PrettyDecoded which avoids percent-encoding and keeps spaces in tact which is not a valid thing to have in a strict URL.
Effectively, we want to ensure a URL is either a valid path to a local file, or one of the special applications (for menu ids), or preferred for preferred applications, like web browser,

BUG: 385727
FIXED-IN: 5.18.0

Is this still good for 5.18?

• Unit tests still pass
• Comes with a new one to verify adding desktop entries with spaces works
• Pinned an application which had spaces in its desktop file to the task bar:
  • Was successfully added with the menu
  • Was successfully merged with the window, if open
  • Was successfully restored/loaded on plasmashell restart
  • Was successfully removed with the context menu
• Created a new activity, pinned an application which had spaces in its desktop file to only one activity:
  • Was successfully restored/hidden when switching activities
  • all of the above