I know the verb bother as in "I didn't bother testing" or the noun bother as in "it's no bother", but this is the first time I encounter this word as a kind of interjection or single-word sentence, written by a native:
Note that in casual testing this 'worked', because backspace deletes the pawn and together. Bother.
What is the meaning of "Bother."? What nuance does it add to the paragraph, which would be missed if it had not been added?
I can't find this usage on Wiktionary.
The context is the following: He is the guy who is managing bugs, so this bug might bother him, or maybe he now regrets that he did not bother writing a more complete test.