Go (or follow a link :) ) to Special:Contributions for a user.
Fill the date range fields. "From date" "To date") and press "Search"

As expected, the results display all edits in the requested date range.
Not expected is that the results include all edits in Topic: namespace prior to the requested date range.

Examples

• https://www.mediawiki.org/w/index.php?limit=500&title=Special%3AContributions&contribs=user&target=Geraki&namespace=&tagfilter=&start=2018-06-01&end=2018-06-15
• https://el.wikipedia.org/w/index.php?limit=300&title=%CE%95%CE%B9%CE%B4%CE%B9%CE%BA%CF%8C%3A%CE%A3%CF%85%CE%BD%CE%B5%CE%B9%CF%83%CF%86%CE%BF%CF%81%CE%AD%CF%82&contribs=user&target=Geraki&namespace=&tagfilter=&start=2018-11-01&end=2018-11-15

Edits in Topic: namespace prior to the requested date range are not included only if you search for edits in a non talk namespace:
https://www.mediawiki.org/w/index.php?limit=500&title=Special%3AContributions&contribs=user&target=Geraki&namespace=1198&tagfilter=&start=2018-06-01&end=2018-06-15

If you do search for edits in a talk namespace then again you get edits in Topic: namespace prior to the requested date range, not all, but Topics included in the requested talk namespace.

• https://www.mediawiki.org/w/index.php?limit=500&title=Special%3AContributions&contribs=user&target=Geraki&namespace=1&tagfilter=&start=2018-06-01&end=2018-12-31
• https://www.mediawiki.org/w/index.php?limit=500&title=Special%3AContributions&contribs=user&target=Geraki&namespace=13&tagfilter=&start=2018-06-01&end=2018-12-31