[praptak]

First of all, it was probably a descriptivist move. What I think happened is that people wrote 'ff' because 'fff' looked like a typo or was less convenient to write, so the linguistics codified that.

Also, there are portmanteau words where the middle letters overlap, e.g. bro+romance=bromance.

[kazinator]

I found a word like this in English.

https://www.etymonline.com/word/chaffinch

There may be others.

When we turn to the letter 'l', we have the word skill-less which is not always written with a hyphen, in which case the three l's remain intact.

[lucb1e]

Bromance does not sound like broromance in speech