Remove the new Slack "rail" containing activity and other useless things

gistfile1.txt

const domObserver = new MutationObserver(() => {
    let rail = document.querySelector('div.p-tab_rail');
    if (rail) {
        rail.remove();
        let old_strip = document.querySelector('div.p-workspace_switcher_prototype div.p-control_strip')
        if (old_strip) {
            old_strip.remove()
        }
        let strip = document.querySelector('div.p-control_strip');
        document.querySelector('div.p-workspace_switcher_prototype').appendChild(strip);
        strip.style.left=0;
        document.querySelector('.p-client_workspace_wrapper').style.gridTemplateColumns = '0 auto';
    }
});
domObserver.observe(document.body, {
    subtree: true,
    childList: true,
});

The paddingBottom was originally 50px. (I'm not quite sure why just removing it once wasn't enough; perhaps it's actually a coincidence and there's another 50px somewhere, but I didn't see any candidates in the computed style from the element inspector.)

This works to avoid hardcoding it:

        let sidebar = document.querySelector('div.p-team_sidebar');
        sidebar.style.height = "calc(100vh - "+strip.offsetHeight+"px - "+getComputedStyle(sidebar).getPropertyValue("padding-bottom")+")";
        sidebar.style.paddingBottom = "0px";

Actually, this needs to be a bit more sophisticated to survive multiple calls to the mutation observer. Here's my attempt (probably better methods are available to those whose javascript knowledge isn't 15 years out of date...):

var sidebarPaddingBottom = "";
const domObserver = new MutationObserver(() => {
    let rail = document.querySelector('div.p-tab_rail');
    if (rail) {
        rail.remove();
        let old_strip = document.querySelector('div.p-workspace_switcher_prototype div.p-control_strip')
        if (old_strip) {
            old_strip.remove()
        }
        let strip = document.querySelector('div.p-control_strip');
        document.querySelector('div.p-workspace_switcher_prototype').appendChild(strip);
        strip.style.left=0;
        document.querySelector('.p-client_workspace_wrapper').style.gridTemplateColumns = '0 auto';
        let sidebar = document.querySelector('div.p-team_sidebar');
        if (sidebarPaddingBottom.length === 0) {
            sidebarPaddingBottom = getComputedStyle(sidebar).getPropertyValue("padding-bottom");
        }
        sidebar.style.height = "calc(100vh - "+strip.offsetHeight+"px - "+sidebarPaddingBottom+")";
        sidebar.style.paddingBottom = "0px";
    }
});
domObserver.observe(document.body, {
    subtree: true,
    childList: true,
});