How to replace the first several characters on multiple lines in Notepad++

Use the "Extended" setting in the Replace window (not "Regular expression": I'm sure there's a way to do it with Regular expression, but using "Extended" works fine).
Enter ".pPrev.\r\n" in the "Find what" field, and leave the "Replace what" field blank. This will include the \r\n characters in the match and delete the whole line.

Toggle the setting View > Show Symbol > Show End of Line

As Xenorose notes, Show All Characters should also be unchecked.

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