The following information is derived from the plugin description.

Transforms text to normalize equal or similar characters.

Normalization is based up on the Unicode Technical Standard #39 which provides a list of characters to normalize with to similar glyphs of the same Unicode string. The plugin allows decomposition of complex characters e.g. ligatures.

Additionally it is able to equalize characters that may have been recognized by OCR. A very common OCR problem is a character combination of 'rn' (r AND n) which is recognized as an 'm'. This filter will normalize any 'm' to 'r n'.