I moved `get_sidebar();` from `header.php` to `footer.php` but it <s>simply does not appear</s> is being placed after the last post in the page body instead of after the footer. There are no errors displayed. What do I need to do to get this working?

functions.php

    /**
     * Register widget area.
     *
     * @link https://developer.wordpress.org/themes/functionality/sidebars/#registering-a-sidebar
     */
    function isometricland_widgets_init() {
    	register_sidebar( array(
    		'name'          => esc_html__( 'Sidebar', 'isometricland' ),
    		'id'            => 'sidebar-1',
    		'description'   => esc_html__( 'Add widgets here.', 'isometricland' ),
    		'before_widget' => '<section id="%1$s" class="widget %2$s">',
    		'after_widget'  => '</section>',
    		'before_title'  => '<h2 class="widget-title">',
    		'after_title'   => '</h2>',
    	) );
    }
    add_action( 'widgets_init', 'isometricland_widgets_init' );

footer.php

    <?php
    	global $path_root, $page_title, $path_img, $path_ssi, $path_css, $path_jav;
    	include_once($path_ssi . 'plugin-paypal.php');
    	include_once($path_ssi . 'plugin-sitesearch.php');
    	include_once($path_ssi . 'plugin-socialicons.php');
    	include_once($path_ssi . 'plugin-norml.php');
    ?>
    				</main>
    				<!-- END PAGE CONTENTS -->
    				<!-- START FOOTERS -->
    				<footer>
    					<div id="footframe">
    						<small class="blk"><?php printf( __( 'Proudly powered by %s.', 'isometricland' ), 'WordPress' ); ?> <?php printf( __( 'Theme: %1$s by Michael Horvath based on %2$s GPLv2 or later.', 'isometricland' ), 'isometricland', '<a href="http://underscores.me/" rel="designer">Underscores.me</a>' ); ?></small>
    						<small class="blk">This page &copy; Copyright 2009 Michael Horvath. Last modified: <?php echo date("F d Y H:i:s", getlastmod()) ?>.</small>
    					</div>
    <?php wp_footer(); //Crucial footer hook! ?>
    				</footer>
    				<!-- END FOOTERS -->
    			</div>
    			<!-- END MIDDLE PANE -->
    			<!-- START SIDEBAR -->
    			<div id="leftframe">
    				<div id="sidebarframetop">
    					<div id="sidebar_widget">
    <?php get_sidebar('sidebar-1'); ?>
    					</div>
    				</div>
    				<div id="sidebarframebot">
    					<div id="file_paypal">
    <?php //echo writePaypalDonate(); ?>
    					</div>
    					<div id="file_search">
    <?php //echo writeSiteSearchForm(); ?>
    					</div>
    					<div id="file_social">
    <?php echo writeSocialIcons(); ?>
    					</div>
    					<div id="file_norml">
    <?php //echo writeNormlLogo(); ?>
    					</div>
    				</div>
    			</div>
    			<!-- END SIDEBAR -->
    		</div>
    	</body>
    </html>

The rendered HTML:

    				</main>
    				<!-- END PAGE CONTENTS -->
    				<!-- START FOOTERS -->
    				<footer>
    					<div id="footframe">
    						<small class="blk">Proudly powered by WordPress. Theme: isometricland by Michael Horvath based on <a href="http://underscores.me/" rel="designer">Underscores.me</a> GPLv2 or later.</small>
    						<small class="blk">This page &copy; Copyright 2009 Michael Horvath. Last modified: February 06 2020 17:03:12.</small>
    					</div>
    <script type="text/javascript">(function(a,d){if(a._nsl===d){a._nsl=[];var c=function(){if(a.jQuery===d)setTimeout(c,33);else{for(var b=0;b<a._nsl.length;b++)a._nsl[b].call(a,a.jQuery);a._nsl={push:function(b){b.call(a,a.jQuery)}}}};c()}})(window);</script><script type='text/javascript' src='https://isometricland.net/blog/wp-content/plugins/syntaxhighlighter/syntaxhighlighter3/scripts/shCore.js?ver=3.0.9b' id='syntaxhighlighter-core-js'></script>
    <script type='text/javascript' src='https://isometricland.net/blog/wp-content/plugins/syntaxhighlighter/syntaxhighlighter3/scripts/shBrushCss.js?ver=3.0.9b' id='syntaxhighlighter-brush-css-js'></script>
    <script type='text/javascript'>
    	(function(){
    		var corecss = document.createElement('link');
    		var themecss = document.createElement('link');
    		var corecssurl = "https://isometricland.net/blog/wp-content/plugins/syntaxhighlighter/syntaxhighlighter3/styles/shCore.css?ver=3.0.9b";
    		if ( corecss.setAttribute ) {
    				corecss.setAttribute( "rel", "stylesheet" );
    				corecss.setAttribute( "type", "text/css" );
    				corecss.setAttribute( "href", corecssurl );
    		} else {
    				corecss.rel = "stylesheet";
    				corecss.href = corecssurl;
    		}
    		document.head.appendChild( corecss );
    		var themecssurl = "https://isometricland.net/blog/wp-content/plugins/syntaxhighlighter/syntaxhighlighter3/styles/shThemeFadeToGrey.css?ver=3.0.9b";
    		if ( themecss.setAttribute ) {
    				themecss.setAttribute( "rel", "stylesheet" );
    				themecss.setAttribute( "type", "text/css" );
    				themecss.setAttribute( "href", themecssurl );
    		} else {
    				themecss.rel = "stylesheet";
    				themecss.href = themecssurl;
    		}
    		document.head.appendChild( themecss );
    	})();
    	SyntaxHighlighter.config.strings.expandSource = '+ expand source';
    	SyntaxHighlighter.config.strings.help = '?';
    	SyntaxHighlighter.config.strings.alert = 'SyntaxHighlighter\n\n';
    	SyntaxHighlighter.config.strings.noBrush = 'Can\'t find brush for: ';
    	SyntaxHighlighter.config.strings.brushNotHtmlScript = 'Brush wasn\'t configured for html-script option: ';
    	SyntaxHighlighter.defaults['class-name'] = 'syntax';
    	SyntaxHighlighter.defaults['pad-line-numbers'] = true;
    	SyntaxHighlighter.all();
    
    	// Infinite scroll support
    	if ( typeof( jQuery ) !== 'undefined' ) {
    		jQuery( function( $ ) {
    			$( document.body ).on( 'post-load', function() {
    				SyntaxHighlighter.highlight();
    			} );
    		} );
    	}
    </script>
    <script type='text/javascript' src='https://isometricland.net/blog/wp-content/themes/isometricland/js/navigation.js?ver=20151215' id='isometricland-navigation-js'></script>
    <script type='text/javascript' src='https://isometricland.net/blog/wp-content/themes/isometricland/js/skip-link-focus-fix.js?ver=20151215' id='isometricland-skip-link-focus-fix-js'></script>
    <script type='text/javascript' src='https://isometricland.net/blog/wp-includes/js/wp-embed.min.js?ver=5.7.1' id='wp-embed-js'></script>
    <script type="text/javascript">(function (undefined) {var _targetWindow ="prefer-popup";
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            outerHeight = window.outerHeight !== undefined ? window.outerHeight : document.documentElement.clientHeight - 22,
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            targetHeight = mobile() ? null : h,
            V = screenX < 0 ? window.screen.width + screenX : screenX,
            left = parseInt(V + (outerWidth - targetWidth) / 2, 10),
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    var isWebView = null;
    
    function checkWebView() {
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    });})();</script>				</footer>
    				<!-- END FOOTERS -->
    			</div>
    			<!-- END MIDDLE PANE -->
    			<!-- START SIDEBAR -->
    			<div id="leftframe">
    				<div id="sidebarframetop">
    					<div id="sidebar_widget">
    					</div>
    				</div>
    				<div id="sidebarframebot">
    					<div id="file_paypal">
    					</div>
    					<div id="file_search">
    					</div>
    					<div id="file_social">
    <div class="social" title="DeviantArt"	><a href="https://posfan12.deviantart.com/"				target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_deviantart.png"	alt="DeviantArt"	/></a></div>
    <div class="social" title="Facebook"	><a href="https://www.facebook.com/michael.horvath.35"			target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_facebook.png"	alt="Facebook"		/></a></div>
    <div class="social" title="Flickr"	><a href="https://www.flickr.com/photos/108839565@N04/"			target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_flickr.png"	alt="Flickr"		/></a></div>
    <div class="social" title="GitHub"	><a href="https://github.com/mjhorvath"					target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_github.png"	alt="GitHub"		/></a></div>
    <br/>
    <div class="social" title="Goodreads"	><a href="https://www.goodreads.com/user/show/67971043-michael-horvath"	target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_goodreads.png"	alt="Goodreads"		/></a></div>
    <div class="social" title="LinkedIn"	><a href="https://www.linkedin.com/in/michael-horvath-45547a116/"	target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_linkedin.png"	alt="LinkedIn"		/></a></div>
    <div class="social" title="Spotify"	><a href="https://open.spotify.com/user/f1703yjwz5hxcrndycvbjfwbl"	target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_spotify.png"	alt="Spotify"		/></a></div>
    <div class="social" title="Wikipedia"	><a href="https://en.wikipedia.org/wiki/User:Datumizer"			target="_blank"><img class="nomagnify" style="margin:0px;" src="https://isometricland.net/images/icon_wikipedia.png"	alt="Wikipedia"		/></a></div>
    					</div>
    					<div id="file_norml">
    					</div>
    				</div>
    			</div>
    			<!-- END SIDEBAR -->
    		</div>
    	</body>
    </html>