|tweet including the word 'ombudsmun'|
It includes the word 'ombudsman', but spelt 'ombudsmun'. I'm a big fan of this spelling. The word contains the word 'man', but as in many words, the syllable is not stressed and the vowel is reduced to a schwa (the sound at the end of my name). The writer has reflected that in the spelling (probably not deliberately, maybe not consciously) by spelling it 'mun'.
For a while, I was spearheading a single-woman campaign to get 'man' to be truly gender-neutral by using terms like 'postman' for female postal workers. In the end I gave up but it remains true that if it's to be reinterpreted either as a suffix (as in postman, policeman, etc) or as just an inseparable part of the word, with no independent meaning, as looks to be the case here, then it has to be the schwa pronunciation rather than the full 'man' vowel. That loss of vowel content hastens its loss of semantic content.
There are other instances of this spelling, even on quite official ombudsman sites (enough that I had to quickly check it isn't actually a variant spelling - seems not). And I ought to also note here that 'man' is used as a pronoun in some varieties of English, such as Multicultural London English, but that it is more or less gendered when it's used in a non-generic 'one' sense (you get some instances of it being used of women, but it's rare). It's also a pronoun in German, in an obviously historically-related turn of events.