Hi @admin t101 thanks for posting in the community! While there isn't currently a feature that highlights objects the way you have described I would recommend using the Layers feature together with the Actions feature to create a similar effect.

With these features you can copy your objects onto a new layer and create a 'button' to toggle layers to show highlighted versions of the objects. I have attached a GIF demonstrating this!

That said we're always looking for ways to improve Lucidchart and your feedback is the best way for us to do that. Would you mind adding your idea(s) to our feature request form? Ideas submitted to this form are passed on to the product development team for their consideration.

I hope this helps! Please let me know if this is not what you are looking for or if you have any questions about this!