Answered: Mobile friendly errors in google search console

This workaround removed the issues in my site. It's based on xrpbro's answer.

Edit the file qa-theme/SnowFlat/qa-styles.css and add the lines in bold:

    .qa-sidepanel {
        display: none;
        width: 280px;
        height: 100%;
        position: fixed;
        right: -280px;
        top: 0;
        overflow-y: auto;
        z-index: 99999;
        background: #fff;
        transition: all 0.15s ease;
        box-shadow: 0 0 0 0 transparent;
    }
    .qa-sidepanel.open {
        display: inherit;
        right: 0 !important;
        transition: all 0.15s ease;
        box-shadow: -5px 0 15px 0 rgba(0, 0, 0, 0.5);
    }

I'm not sure if "display: inherit" is the most correct option, but it works fine in all the scenarios I've tested it. Feel free to suggest a better display option.

This change removes the smooth transition of the side panel, but keeps Google happy. My guess is that having the side panel visible but outside of the screen is what Google detects as mobility errors. You can check out the result here:

https://support.vehiclephysics.com/69/how-can-import-tir-pacejka-file-which-has-pac2002-file-format

That page was showing the errors "Clickable elements too close together" and "Content wider than screen".