Player can hide an image by shooting a fire arrow at the image.
Other players feel uncomfortable with these issues. can it fixed?

Well, for better or worse, that's just how the game works. I prefer to avoid changing the behavior of existing game mechanics to not break other plugins or game worlds as some players might rely on arrows behaving like that.

There's a really simple solution, though: just remove the blocks behing the image. The image will still be rendered and there will be no block for arrows to attach to.

Well, for better or worse, that's just how the game works. I prefer to avoid changing the behavior of existing game mechanics to not break other plugins or game worlds as some players might rely on arrows behaving like that.

There's a really simple solution, though: just remove the blocks behing the image. The image will still be rendered and there will be no block for arrows to attach to.

arrow fire was still attacted itemframe although block was not behind.

Well, there's not much we can do in Yamipa. Because the image is not really there in the world, the Minecraft server will calculate the position of the arrow being thrown in a different place:

As such, Yamipa (the plugin) will not get the event for an arrow hitting the image.

My advice would be to use a different plugin to prevent the usage of bows in a particular world area.