This is a follow-up to problems we've had with on-screen display of fonts, where the spacing between words and cursor position was not calculated correctly due to ligatures, swooshes, or other font features. My guess is that the fix to that problem was too general, creating problems with monospaced fonts.
In a LyX document, insert ERT, and enter a string of (for example) "m"s, filling up most of the line. For me with all mono-spaced fonts I've tried, the cursor position gradually moves too far to the right, leaving a gap between it and the last "m". Moving the cursor to the left and typing inserts the new characters in an unexpected position. This seems to work for all characters *except* lower-case "f", which results in the cursor being properly positioned. Thus, position the cursor at the end of the long string of "m"s (so that there is the gap between the cursor and the last "m"). Now type two "f"s: the first one appears immediately to the right of the last "m", with the cursor still placed too far to the right, but the second one appears after a gap and immediately to the left of the cursor. Let me know if you want screenshots. BH
