Strange result with HOCR output, from 2 similar input images

[D. Vivus]

In the attached 7z file, there're 2 TIFF images and 2 hocr output files' produced by cuneiform-1.0.0 linux-x86_64

The file test_2.tif was modified from test.tif, the text (i<subscript>r</subscript>) in the beginning of 9th line in the test_2.tif was shifted slightly to the right as in the test.tif

And, the result, the output ocred texts, line 16 (correspond with 9th line of the image), of different images are different. The BBOX parameters of this line are different, and that's incorrect result produced from the original images (test.tif)