The "Duration" property of a scene rounds floating point numbers to the nearest integer. So a value of 1.5 is displayed as 2. But when you click in the field to edit, it jumps back to 1.5. The request is to make the displayed value be the exact value rather than a rounded value. (
This is particularly made worse when a recording gets extended by a few frames. The scene length can be extended without you even realizing. (Should be a quick change.)