forced page break
Computing term for a manually inserted page break, as opposed to an automatic one.
To insert a forced page break in a Word document, press Ctrl+Enter.
改ページ is a general term for page break, which can be automatic or manual. 強制ページ区切り specifically refers to a forced (manual) page break.
Compound of 強制 (forced) + ページ (page) + 区切り (break, delimiter). A straightforward technical term.