Add custom attributes support, e.g. 'download'

Alternatively, we could add a submodule which allows to define the attributes to fill with values, so we don't have to provide them explicitly?

If I understood you correctly you can add custom attributes here "/admin/config/menu_link_attributes/config"
See attached screenshots

Thanks @Igor Mashevskyi, seems you're right and this is already possible. See this class: https://git.drupalcode.org/project/menu_link_attributes/-/blob/8.x-1.x/s...

@kay_v: I'll close this issue, please reopen if we got you wrong and this is not, what you were looking for!