I am not sure I would consider using dev tools as a correct answer. That will not work for your average business user.
Being a touch friendly interface it is not easy for a UX perspective for a user to highlight a value, as it then is interpreted as a selection. This means you can not accomplish browser based highlight-copy behavior.
The object context menu not offer copy as an option. This might seem trivial, but I am not sure copy would be that easy to implement so that it works with all browsers and devices. I guess this is partly the down side with modern ecosystems.
While the copy option is not available I would suggest looking at theses options;
Export table to Excel. Which might be a decent option when copying multiple values.
Qlik Sense widget can be setup to show a read only view, which allows copy paste through browser