Question 1

How does the duplicate detection work?

Accepted Answer

Each line is compared as a string. Two lines are duplicates if they are character-for-character identical (case-sensitive by default). The first occurrence is kept; subsequent duplicates are removed. Enable case-insensitive mode to treat 'Apple' and 'apple' as duplicates.

Question 2

Are blank lines counted as duplicates?

Accepted Answer

Yes. Multiple consecutive blank lines are treated as duplicate empty strings and reduced to one (or zero, if the 'remove blank lines' option is enabled). This normalizes whitespace in the output.

Question 3

What is the maximum list size this handles?

Accepted Answer

Processing happens in your browser. Lists up to ~100,000 lines work smoothly. Very large inputs (millions of lines) may be slow. For large-scale deduplication, command-line tools like sort -u or awk are more suitable.

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