Created attachment 97928 [details] Screenshot If there is at least 1 fullwidth character (e.g. hiragana, katakana, kanji, hanzi, fullwidth latin etc.) in name of window, then text of name of this window is moved downward. Examples of how to have window with such character: - Open e.g. https://en.wiktionary.org/wiki/%E3%81%82 in web browser. - Set format of name of active tab in Konsole to e.g. "ａ". I attach screenshot showing this problem for text of name of window of Firefox.
Created attachment 97935 [details] Example with proper font This probably just happens because your main UI font doesn't have those glyphs, so the text rendering stack fetches them from a different font, which will change the metrics for a given line to be the union of the metrics of the two fonts and can also lead to text layout problems. To avoid problems like this I recommend using a UI font with wide character coverage, e.g. Plasma 5's default font Noto Sans, which was chosen for reasons like this. I've attached a screenshot of Plasma 5.6 using Noto Sans as an example.