Linked words disappear in mobile and tablet.

I don’t know exactly when this started, but in the last week I have noticed that linked words on my site disappear when viewed on mobile and tablets. They still work fine on larger screens. If I try to make a new link, that word disappears.If I remove the link the words reappear. I have never experienced this behavior before and I’m extremely puzzled. Please help me understand how this can happen.

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