URLs in widget/sidebar only break/hyphenate/wrap after the second-last slash (/)

Dear wordpress community,

Yesterday I installed a self-hosted wordpress (https://tinyurl.com/35gnhot) and somehow the listed URLs in the widget/sidebar only break/hyphenate/wrap (however you want to call it) after the second-last slash (/).

In Chrome:
I see the URL going beyond the sidebar width (whereas my text widget stays between borders just perfectly) and it breaks to another line after the second-last slash (/) or first hyphen (-) it encounters.

In IE:
I see the URL until the right sidebar border and that what exceeds this border disappears. On the line after you see the rest of the URL (that what breaks after the second-last slash (/) or first hyphen (-)

What I tried
I tried using the WP-Typography plug-in because it has some hyphen control. However, this unfortunately did not solve the problem.

Hope you can help me out as I have limited HTML/CSS skills.
If you need more clarification (e.g. through images), please do ask for it and I will answer almost immediately.

Kind regards,

Peter

PS: irrelevant to the topic, but does somebody know a good way to make my blog completely private? Maybe with a login screen that protects every page?