Thunderbird and Links in PDF Documents - Okular

Running 42.2 with KDE desktop and using Thunderbird as browser.

Recently I have had to look at a pdf document available on a website. I have Okular set up as the application to use within Thunderbird so the pdf opens in Okular.

Within the pdf document are various further url links. These are shown in blue and underlined as though they were active but they are not.

How may I view a pdf document so that links within it work as active links and if I click on them I am taken to the site?

Budgie2

Are you sure that this is not a problem with the PDF generator? There are a lot of PDF generators out there - mostly for a certain legacy system - which create an image of a text document or just a text rendering of it rather than creating a link.

There are also unskilled users of desktop publishing programs who do not know how to insert links into documents.