Choose two versions
In the diff tool, open the original and modified files separately or paste both texts. Each file has its own decoding selection. The editor can also compare current text to the version opened or last reset as a sample. The comparison operates on decoded lines, not raw file bytes.
Read the result
Removed lines use a minus marker, added lines a plus marker and unchanged lines a space. Color is supplementary. The tool uses a longest common subsequence comparison up to 800 lines per side and 250,000 characters total. Larger inputs show an explicit limit message rather than an inaccurate diff.
What a diff cannot decide
A diff tells you what changed, not whether the new setting is supported. Line endings are normalized before comparison, so use the download options to choose the final endings. Test every meaningful change in the application that reads the file.