See the first example in the attached testcase, compare it to the second. The first example has a slightly greater spacing between the icons, but the overall width of the grey area is the same, leading to a linebreak. I assume that if the extra spacing would be added to the width the line break would not occur. If you fix bug 304355 before this: the same applies if you have this in an :after pseudo-element. Reproducible: Always
Created attachment 72858 [details] CSS content testcase
Dear user, KHTML (and KJS) was a long time more or less unmaintained and got removed in KF6. Please migrate to use a QWebEngine based HTML component. We will do no further fixes or improvements to the KF5 branches of these components beside important security fixes. For security issues, please see: https://kde.org/info/security/ Sorry that we did not fix this issue during the life-time of KHTML. Greetings Christoph Cullmann