I believe that this problem is caused by failing to leave a blank line after the image. Which is a standard in the Markdown language. Because Hive uses Markdown for saving text. Then frontends convert it to HTML. But different frontends use different converters. So PeakD have tweaked their converter to handle the missing blank line. As have Ecency. But if you want consistent results across all frontends, you should stick to basic Markdown rules.

Unfortunately, I can't find an article that explains this on Hive. Though I know that I have read one here before. Anyway, the thing that stood out for me is that different "blocks" of content should always be separated by blank lines. So this applies to images, headings, lists etc.

Of course, many Hive frontends allow HTML as well as Markdown. But it's always risky to mix the them. So if you don't want to use blank lines around images, you can switch to the < IMG > tag instead.