I’ve been using Firefox for a while to read 2 APOD articles a day. Lately, when I opened the usual archive link to click on articles, I found that the 2 I’d seen the day before were not marked as ‘read’ (colored purple). Thinking I must have deleted the browser’s recent history on accident, I went on as normal. But today, as I accessed it, all 4 articles I visited yesterday and the day before appeared as blue links. When I clicked on the June 12 & 13 ones, they promptly turned purple, just like yesterday with the June 10 & 11; but I bet that if I close the tab and open it tomorrow morning, they’ll be blue again. It’s like time itself has frozen on June 7 for this webpage!
I don’t frequent other pages with timestamps as obvious as NASA’s APOD, so I don’t know for sure if this Groundhog-Day scenario happens with all websites or not. What I’m certain of is I didn’t erase history yesterday, and I don’t run any files that execute that browser’s function. A round of quick scan using local antivirus returned negative result. 1 thing of note is that my C: drive was nearly full, so I chose “Compress this drive to save disk space” option in Properties to increase the free room to 3GB. But the weird phenomenon happened to Firefox before the compressing action.
Any ideas of what’s going on? If there’s a chance of my computer being manipulated remotely, how can I discover it?