JavaScript bookmarklet to click an element and copy its text contents. See https://makandracards.com/makandra/46962

copy-element-text-bookmarklet.js

var overlay = document.createElement('div');
Object.assign(overlay.style, {
    position: 'fixed',
    top: 0,
    left: 0,
    width: '100vw',
    height: '100vh',
    zIndex: 99999999,
    background: 'transparent',
    cursor: 'crosshair'
});
document.body.append(overlay);

function copyToClipboard(textToCopy) {
    // navigator clipboard api needs a secure context (https)
    if (navigator.clipboard && window.isSecureContext) {
        // navigator clipboard api method'
        return navigator.clipboard.writeText(textToCopy);
    } else {
        // text area method
        let textArea = document.createElement("textarea");
        textArea.value = textToCopy;
        // make the textarea out of viewport
        textArea.style.position = "fixed";
        textArea.style.left = "-999999px";
        textArea.style.top = "-999999px";
        document.body.appendChild(textArea);
        textArea.focus();
        textArea.select();
        return new Promise((res, rej) => {
            // here the magic happens
            document.execCommand('copy') ? res() : rej();
            textArea.remove();
        });
    }
};

function getElement(event) {
    overlay.style.pointerEvents = 'none';
    var element = document.elementFromPoint(event.clientX, event.clientY);
    overlay.style.pointerEvents = 'auto';

    return element;
}

document.addEventListener('mousemove', function(event) {
    var element = getElement(event);
    if (!element) return;

    var position = element.getBoundingClientRect();

    Object.assign(overlay.style, {
        background: 'rgba(0, 128, 255, 0.25)',
        outline: '1px solid rgba(0, 128, 255, 0.5)',
        top: '' + position.top + 'px',
        left: '' + position.left + 'px',
        width: '' + position.width + 'px',
        height: '' + position.height + 'px'
    });
});

overlay.addEventListener('click', function(event) {
    var element = getElement(event);
    var text = element.textContent || element.value;
    text = text.replace(/\n[ \n]+\n/g, "\n").replace(/\n\n+/g, "\n\n").replace(/^\n+|\n+$/g, '');
    if (!text.match("\n")) text = text.replace(/^ +| +$/, '')

    copyToClipboard(text);
    document.body.removeChild(overlay);
});

Minified Version

javascript:void function(){function a(a){if(navigator.clipboard&&window.isSecureContext)return navigator.clipboard.writeText(a);else{let b=document.createElement("textarea");return b.value=a,b.style.position="fixed",b.style.left="-999999px",b.style.top="-999999px",document.body.appendChild(b),b.focus(),b.select(),new Promise((a,c)=>{document.execCommand("copy")?a():c(),b.remove()})}}function b(a){c.style.pointerEvents="none";var b=document.elementFromPoint(a.clientX,a.clientY);return c.style.pointerEvents="auto",b}var c=document.createElement("div");Object.assign(c.style,{position:"fixed",top:0,left:0,width:"100vw",height:"100vh",zIndex:99999999,background:"transparent",cursor:"crosshair"}),document.body.append(c);document.addEventListener("mousemove",function(a){var d=b(a);if(d){var e=d.getBoundingClientRect();Object.assign(c.style,{background:"rgba(0, 128, 255, 0.25)",outline:"1px solid rgba(0, 128, 255, 0.5)",top:""+e.top+"px",left:""+e.left+"px",width:""+e.width+"px",height:""+e.height+"px"})}}),c.addEventListener("click",function(d){var e=b(d),f=e.textContent||e.value;f=f.replace(/\n[ \n]+\n/g,"\n").replace(/\n\n+/g,"\n\n").replace(/^\n+|\n+$/g,""),f.match("\n")||(f=f.replace(/^ +| +$/,"")),a(f),document.body.removeChild(c)})}();