Solution
Try adding this to your extra.less:

Code:
@media (max-width: @xf-responsiveMedium)
{
    .message:not(.message--forceColumns) .message-user
    {
        display: flex;
        flex-wrap: wrap;
    }
    .message:not(.message--forceColumns) .message-userExtras
    {
        display: block;
    }
}
@media (max-width: @xf-responsiveNarrow)
{
    .message:not(.message--forceColumns) .message-userExtras
    {
        flex: 1 1 100%;
    }
}
Try adding this to your extra.less:

Code:
@media (max-width: @xf-responsiveMedium)
{
    .message:not(.message--forceColumns) .message-user
    {
        display: flex;
        flex-wrap: wrap;
    }
    .message:not(.message--forceColumns) .message-userExtras
    {
        display: block;
    }
}
@media (max-width: @xf-responsiveNarrow)
{
    .message:not(.message--forceColumns) .message-userExtras
    {
        flex: 1 1 100%;
    }
}
 
Solution

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