This appears to be a known issue with PDF export, I found several references with a quick Google search. For PDF export, it seems to particularly be a problem with dark backgrounds. (It’s possible that people with lighter backgrounds simply don’t notice the problem)
I can’t find a specific reference for just exporting the visual - but it makes sense to me that the same problem would exist. If you need a version of this chart for export, I would recommend creating a copy of the chart without the dark background.
Hi @nipunadv. I disagree … I don’t think its a bug at all; its just the way Power Bi operates. If you use Focus Mode on any visual from a page that uses, for example, a dark background and white text, the text on the now-focussed graphic is unreadable. You need to apply the dark background to the visual itself (not the page background) in order for focus mode to render your graphic, and perhaps that’s the same for export to PowerPoint.
Greg