I would like to know if the word "repack" exists at least in one of the variants of the English language (i.e. British English, American English and so on), and if yes, if it can be hyphenated at the end of a line.
Personally, I believe that it exists, because I have read it several times in various articles. But I am completely unsure if it can be hyphenated at the end of a line. On one hand, Merriam-Webster does not know that word at all, Wiktionary knows it, but doesn't say anything about hyphenation, and no online hyphenation service I have tried does hyphenate it.
On the other hand, my personal feeling is that it might be possible to hyphenate it like "re-pack" at the end of a line.
Please note that I am not asking how to spell it when using it in normal text flow, i.e. if it is in one line. I am only interested in separating the word at a line end.
To make it absolutely clear, let's take another word as an example: You may hyphenate the word "power" like "pow-er", but not in normal text flow, i.e. if the word fits into the current line, but only at the end of a line, having the string "pow-" at the end of one line and the string "er" at the beginning of the next one. Of course, writing "pow-er" in the normal case, i.e. not at a line break, is wrong.
So, coming back to my actual problem, I would like to know if I can have "re-" at the end of one line and "pack" at the beginning of the next line even if no dictionary and no online hyphenation service does hyphenate that word.
Could anybody explain which rules apply here (of course, before asking, I have read some articles that gave some general guidance and that made me assume that the word in question could be hyphenated at line ends like shown above, so I just don't get why none of the online services hyphenates that word) or give a reference to a source where I can lookup correct line end hyphenations for English words (the word I have asked for is just an example - since I'm currently translating my website from German to English, there are hundreds of such cases, i.e. words whose line end hyphenation seemingly isn't shown at any source I know and which are not hyphenated by online services although I strongly believe they should).
All links I have seen in the comments so far are definitely not duplicates of my question. Without exception, they all deal with the question how you should write the respective word under normal circumstances, i.e. without a line break taking place.