I have seen here how to perform a page break:
I have been trying to find the equivalent but for columns in a .2C two columns formatted document. Sometimes the header of a section appears at the end of the left column isolated and I would like to manually force to appear at the beginning of the right column in those cases.
Is there any equivalent to .bp but for columns?
You can use the basic troff need command. It takes the number of lines of space you need for the following input. Typically, a header macro would include such a command to avoid the widow that you are seeing. So if you would like at least 2 lines of text plus a header you might use, say
.ne 5
.ne 999 will always trigger a new column, but I suppose the ms equivalent is the register HORPHANS (lines to keep with header). You could always consider a floating keep .KF so that the text stays in column 1 and the image floats to column 2, to avoid big gaps.
.ne 999 definitively works, so it is a valid workaround to force a column break