In a section explaining Chinese punctuation, we have the above sentence. Importantly, the sentences doesn't end in a 句号. The other examples in this textbook likewise omit a 句号 after ellipses. Judging from this, it seems it is standard to omit the 句号 after a 省略号.
Omitting the 句号 seems like a bad idea to me: it's unclear where the sentence ends; compare:
For this reason, I strongly prefer to add a 句号, like how I would add a 引号 or 括号.
Question: Is it acceptable to add a 句号 (full stop 。) at the end of a sentence ending in a 省略号 (ellipsis ……)?