Using Chrome at Windows I used the following javascript/bookmarklet to open a popup with given size:

javascript: try {
    s = window.getSelection();
    if (!s || s == '') {
        for (i = 0; i < frames.length; i++) {
            s = frames[i].window.getSelection();
            if (s && s != '') break;
        }
    }
} catch (e) {}
if (!s || s == '') void(s = prompt('Please select a word before you click on this link (or type your text here:)', ''));
if (s && s != '') {
    dw = window.open('http://pocket.dict.cc/?bm=1&s=' + encodeURI(s), 'dict', 'width=320,height=480,resizable=yes,scrollbars=yes');
    dw.focus();
}

Trying to do the same in Chrome at MacOS instead of the popup new tab is opened.

Is there any way to open a popup with the size, given in popup settings (width=320, height=480)?