standalone document class: "border" option does not work as expected

Question

• I want a standalone diagram (standalone document class plus pgfplots package).
• I want that the diagram doesn't dance around when I have multiple diagrams with different axis limits and so on.
• Therefore I use scale only axis and trim the bounding box to the axis (see MWE).
• All works fine but the border option of the standalone package seems not to work.
• border = {15mm 0mm 0mm 0mm} % left bottom right top should add a border to the left side but it adds a border to all four sides.
• The yellow background is only to make the example clearer.

---

% https://tex.stackexchange.com/questions/123880/
\documentclass[
    tikz,
    border = {15mm 0mm 0mm 0mm} % left bottom right top
    ]
    {standalone}

\usepackage{pgfplots}
\pgfplotsset{compat=newest}

\begin{document}

\begin{tikzpicture}
    \begin{axis}[
        xlabel = $x$,
        ylabel = {$y$},
        xmin = 0,
        xmax = 30,
        ymin = 0,
        ymax = 100,     
        xtick = {0,10,...,30},  
        ytick = {0,10,...,100}, 
        scale only axis,
        % https://tex.stackexchange.com/questions/153708/
        execute at end picture={
            \pgfresetboundingbox
            \path (current axis.north west) (current axis.south east);
        },  
        % https://tex.stackexchange.com/questions/239294
        axis background/.style={fill=yellow}    
    ]
    %
    \addplot[]{x^2};        
    %       
    \end{axis}
\end{tikzpicture}

\end{document}

---

border = {0mm 0mm 0mm 0mm}

---

border = {15mm 0mm 0mm 0mm}

Answer 1

The option is a bit picky regarding spaces. Compare:

\documentclass[
    border={15mm 0mm 0mm 0mm},% works
   % border= {15mm 0mm 0mm 0mm}%wrong borders
    ]
    {standalone}
\begin{document}
\rule{1cm}{1cm}
\end{document}