Visual artifact when using, for example, Courier New 10

[janwilmans]

you can see the last pixel-line from line 16 being drawn at the top of the screen. workaround: restart debugview++ after changing the font.

reproduce:

• set the font to Courier New 10
• close debugview++
• open debugview++
• set the font to Courier

now the lines should be shifted vertically by 1 of more lines

• close debugview++
• open debugview++

effect gone, vertical alignment ok.