If the code is like this:
text text text text text.~\cite{sour}\begin{figure}[htbp] \centering \includegraphics[width=0.9\textwidth]{IMG/fig} \caption{Caption.} \label{fig:figlabel} \end{figure} No additional vertical space between the figure and the text text text.~\cite{sour} appears. If the code looks like this(what i usually use):
text text text text text.~\cite{sour} \begin{figure}[htbp] \centering \includegraphics[width=0.9\textwidth]{IMG/fig} \caption{Caption.} \label{fig:figlabel} \end{figure} There appears additional space. The text text text.~\cite{sour} is (randomly) as long as one textline, every word i add to the text solves the problem (the text wraps then). It seems the reason is because the text is just about to wrap.
\begin{figure}[htbp]not starting on a new line in the first code snippet?\begin{figure}[htbp]is attached to the text, there appears no vertical space. The linebreak (in Texstudio) leads to the bug.