Spacer extension

[Sibelius58]

I am just writing to ask if there is a possibility to vary the (horizontal) space between icons (extensions) on the toolbar (or other bars). If not, I ask, as a layman, if it is not possible to work out an extension that introduces space between icons (extesions), a spacer, in short.
Thanks, regards

[ccfs]

Use "User style sheet" add-on:

The above example adds 2 pixels at the left and right of each button. You can refer to "script\index.css" for the default settings.

You can use a tool bar button to open the add-on settings page quickly:

see:
TE Add-ons in Categories PDF
https://www.w3schools.com/css/css_padding.asp