A well known limitation is look behind assertions, but I don’t recall seeing anything about lazy quantifiers before.
Perhaps you could provide an example expression, source text, result and expected result, with a link to the online checker(s) you are using?
Trying to provide the needed information I realized where the problem was: I am parsing a webpage, and what Request(url).loadString() returns somewhat different than the sourcecode of the Page itself.
Using the returned string in the regexp Tester is kow consistent.
Interesting that this comes up now after having done a couple of regexp matches already…
Nevertheless, thank you for your answer, brought me on the right track…