Are there 'up page and down page arrows' available as add-ons anywhere for Linux users?

I ask as i'm used to having them via the Opera browser i have. However since starting to use a more up to date version of it, these are no longer available, so i thought maybe i could get some via Linux?
I used these things more than anything else and i miss them.

Linux Mint Serena 18.1 MATE.

Hi...

Are you referring to scroll arrows? If so, I was able to find some information about that here. You can also look through my Google search here.

In terms of an add-on or extension, take a look through here and see if anything helps.

Regards...

In Mint 18.1 you have GTK 3.18.9-
That brings with it changes to the scroll bars from previous versions. And it is not exactly a trivial task to return to the old style.

Since GTK+ 3.15, overlay scrollbars are enabled by default, meaning that scrollbars will be shown only on mouseover in GTK+ 3 applications.
This behavior can be reverted by setting the following environment variable: GTK_OVERLAY_SCROLLING=0.

See Environment variables#Graphical applications.

Remove overlay scroll indicators
The positions of the overlay scrollbars are indicated by thin dashed lines in the application window. These dashed lines will be present even when overlay scrolling is disabled using the environment variable discussed in the section above. To remove the indicator lines, create the following file:

~/.config/gtk-3.0/gtk.css
/* Remove dotted lines from GTK+ 3 applications */
undershoot.top, undershoot.right, undershoot.bottom, undershoot.left { background-image: none; }

https://wiki.archlinux.org/index.php/GTK%2B

But please be aware that you will see the scroll bars when you hover the mouse on the dotted lines - they just disappear when you move the mouse off that location.