As you show Post titles displaying vertically, each letter in the title below the previous one. so its easy solution here in below step by step guide.
1. Open posts from dashboard.
2. Click all Posts.
3. Then click screen option as shown in below picture.
4. In post option unchecked some options.
5. All Done, as you unchecked options your post vertical words goes to up inline position horizontally, as you show in below my post titles.
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