[BUG] Individual replacements don't work with regex lookbehind

[aaaxx]

Description of the Issue

If there's a lookbehind in the search string, clicking the "Replace" button will skip to the next match without replacing anything. (Using "Replace All", however, works fine and replaces all matches.)

Steps to Reproduce the Issue

Try searching for something like (?<=a). and replacing it with something by clicking the "Replace" button.

Debug Information

Notepad++ v6.9.2
Build time : May 18 2016 - 00:34:05
Path : D:_D - apps\Notepad++ Portable\App\Notepad++\notepad++.exe
Admin mode : OFF
Local Conf mode : ON
OS : Windows 8.1
Plugins : combine.dll ComparePlugin.dll DSpellCheck.dll ElasticTabstops.dll IndentByFold.dll mimeTools.dll NppConverter.dll NppExport.dll NppFTP.dll NppTextFX.dll PluginManager.dll ScrollPastEOFUni.dll SnippetPlus.dll

[MetaChuh]

please update your notepad++ to the latest version Notepad++ 7.6.6 and migrate or reinstall your plugins if you update from version 7.5.9 or below.
if your issue still persists, and it is still of relevance to you, please feel free to file a new issue as easy to understand and reproducible as possible.

thank you for your help and best regards.

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[sasumner]

Lookbehind can't reasonably work when finding matches one at a time. Replace All is the best strategy here.