Regular expression search to find lines beginning with same characters
You can run a Regex search which will find consecutive lines that begin with the same characters. This search:
^((.{10}).*)(?:\r?\n\2.*)+
. . . will check the first 10 characters at the beginning of a line and check to see if the same 10 characters appear at the start of the next line.
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. . . adding $1 in the replace window will remove each duplicate line.
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