Testing version: Bear 2 beta (9772)
What were you doing: editing notes
What happened: the notes on the second pane blinks
I figure this happens only when the note contains an image, and can be shown from the second pane. Any form of editing cause the second note pane (specifically the image) to blink.
This is not a bug, the images’ thumbs in the notes’ preview are loaded asynchronously, and the preview is reloaded when the note is saved (a couple of seconds after you end editing). The flash is the effect of the placeholders being replaced by the images’ thumbs, even if it’s fast it’s still noticeable.
We’ll try to minimize the visual effect 
But this is not the case in Bear 1.0.
Would it be just optimisation issue then?
Here is a video for better representation; (sorry for the blurriness, the file size was too big)
For me, it doesn’t load (i.e., flash) the images’ thumbs only after ending editing on a tag. The thumbs flash after ending editing on any text. If I stop typing/editing for one second, the thumbs flash.