When using a hyphenated compound word (i.e., a compound adjective, verb, or noun) in a document and the word splits across two lines due to it being at the end of a line, is it considered improper to split it across lines and should one instead force it to the next line with a non-breaking hyphen?
For example, the compound adjective self-supporting:
A good mat for this purpose should have enough rigidity such that the mat is self‑
A good mat for this purpose should have enough rigidity such that the mat is
In other words, should one use a non-breaking hyphen in compound words so that the reader does not mistake the word for not being compound (e.g., selfsupporting) and just broken at a syllable due to being at the end of the line?