Hi, At the end of your prompt you emit \e[37m, that is, change to the 7th palette color (typically light gray), rather than the default color of your emulator. That is, the status at the beginning of executing your command, the status used for the letter "A" is not the default status, not the one which you achieve using tput sgr0 or \e[m or \e[0m. This explains why "B" and "D" don't have the same attributes.
Go to GNOME Terminal's preferences, switch to the Colors tab under your profile. You'll find the "Default color" (potentially overridden by "Use colors from system theme"), this is what sgr0 a.k.a. \e[m switches to. You'll also see the 2x8 "Color palette" entries, the upper right of them is selected by \e[37m. Even if these two have the very same RGB value, they might behave differently when combined with the ambiguous "bold/bright" flag. VTE 0.54 changed a couple of things in how it handles colors. The changes were intentional, made in the direction of separating the bold attribute from the colors. The bold counterpart of the default color used to be an automatically generated brighter variant of that color. If your default text color is a light shade of gray, the automatically generated brigher variant was most likely #FFFFFF. It's no longer the case, the combination of the bold flag with the default text color still uses the exact same text color, just with bold font. If you preferred the old behavior of making the text brighter, you should set whatever color you'd prefer here as the "Bold color". For the 7th palette color, the bold variant used to switch to the 15th palette color (the one shown underneath). Beginning with 0.54 this behavior is no longer mandatory, can be switched off by disabling "Show bold text in bright colors". (By the way, starting with 0.56 it'll be disabled by default for new users. The same checkbox will remain there for users to re-enable switching to the brighter counterpart.) I hope this clarifies what's going on. cheers, egmont