Rated 5 out of 5 stars

Thank you very much! I've been filing and deleting emails by mistake for 2 years, because of that mania of putting single-letter hotkeys. What a crazy idea.

And, as sayed by Frederik below,...
You can paste the following into the settings box to really completely disable all one-letter shortcuts:

"0": "unset",
"1": "unset",
"2": "unset",
"3": "unset",
"4": "unset",
"5": "unset",
"6": "unset",
"7": "unset",
"8": "unset",
"9": "unset",
"j": "unset",
"k": "unset",
"o": "unset",
"f": "unset",
"#": "unset",
"r": "unset",
"a": "unset",
"x": "unset",
"c": "unset",
"u": "unset",
"b": "unset",
"m": "unset",
"p": "unset",
"s": "unset",
"t": "unset",
"w": "unset",
"]": "unset",
"[": "unset"

Léirmheas ar leagan níos sine den bhreiseán seo (2.1.0).