I see the same on that page. I think that it as a problem with a remote (downloaded) font (Yrsa) that the web page uses because it looks OK when I remove that font from the font-family specification.

You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected.

You can check the font used for selected text in the Font tab in the right pane of the Inspector.

That does appear to be the problem. A different website I found with the same problem also uses the Yrsa font.

Is this a bug in Firefox's font rendering, or in the Yrsa font? It renders correctly in Chromium.

Another rendering issue I noticed when comparing the page linked above to Chromium is that the first letter of the lead is supposed to have a red background. Inspecting the element in Firefox shows some complicated CSS rules that should give a red background, but it clearly doesn't work. Could this be related to the Yrsa font rendering issue, or is it just a coincidence?

I don't know that much about font issues, but it looks that the two character 'ij' next to each other are treated as one character. If I type 'ijj' then I see a correct 'ij', so this could be an issue with ligatures.

I do see the read box if I disable the content: ; rule, but I don't know why this works.

Hallo daar

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