Does WordPress’s PHP DOMDocument loadHTML not preserve <BR /> lines in posts content & how to fix?

PHP DOMDocument loadHTML doesn’t keep tabs/lines generated by <br />, instead it merges them and removes the <br /> breaks.
I’m using the below code to slightly change the WordPress’ posts content. Everything works fine except for the fact that the lines of text are not echoed as they are, separately. Instead, they are echoed in a single line/tab, making the text hard to read.

For example, what I’d like to see is this:

Specifications:
Name: VR glasses
Type: virtual reality glasses
Model: for VRGPRO+
Lens type: blue coated lens

But what I see instead is:

Specifications:Name: VR glassesType: virtual reality glassesModel: for VRGPRO+Lens type: blue coated lens

I have no idea how to fix this. I’ve tried removing all the LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NOBLANKS but the result is the same. I’ve also tried the indentation fixes from here, plus other similar posts. Still no luck. Please help.

Here’s the code from the WP theme:

$dom = new DOMDocument; 
            
$dom->loadHTML(strip_tags(mb_convert_encoding(get_the_content(), 'HTML-ENTITIES', 'UTF-8'), '<img>,<div>,<table>,<thead>,<tbody>,<tfoot>,<tr>,<th>,<td>,<ul>,<ol>,<li>,<strong>,<em>,<h3>,<h4>,<h5>,<h6>,<p>'), LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NOBLANKS);
        
$xpath = new DOMXPath($dom);
            
            
foreach ($xpath->query('//@*[not(name()="src")]') as $attr) {
     $attr->parentNode->removeAttribute($attr->nodeName);
}
$images = $dom->getElementsByTagName('img');
        foreach ( $images as $image )
        {
$properlink = rtrim(preg_replace ('//','https:',$image->getAttribute('src'),1),'/');
                $image->setAttribute( 'alt', esc_attr( wp_trim_words( get_the_title(), 10,'') ) );
    $image->setAttribute( 'data-src', $properlink );
                $image->removeAttribute('src');
$image->setAttribute( 'style', 'width:100%;max-width:100%;' );
        }
while (($node_list = $xpath->query('//*[not(*) and not(@*) and not(text()[normalize-space()])]')) && $node_list->length) {
    foreach ($node_list as $node) {
       $node->parentNode->removeChild($node);
    }
}
echo $dom->saveHTML();

Update 1:

This is the input, in the WP post the
is present, although they’re all in one line:

Specifications:<br />Name: VR glasses<br />Type: virtual reality glasses<br />Model: for VRGPRO+<br />Lens type: blue coated lens<br />

Update 2:

Specifically allowing the BR in the strip_tags did’t help much:

$dom->loadHTML(strip_tags(mb_convert_encoding(get_the_content(), 'HTML-ENTITIES', 'UTF-8'), '<img>,<div>,<table>,<thead>,<tbody>,<tfoot>,<tr>,<th>,<td>,<ul>,<ol>,<li>,<strong>,<em>,<h3>,<h4>,<h5>,<h6>,<p>,<br>'), LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NOBLANKS);

• this breaks everything and no input is echoed (blank page)

$dom->loadHTML(strip_tags(mb_convert_encoding(get_the_content(), 'HTML-ENTITIES', 'UTF-8'), '<img>,<div>,<table>,<thead>,<tbody>,<tfoot>,<tr>,<th>,<td>,<ul>,<ol>,<li>,<strong>,<em>,<h3>,<h4>,<h5>,<h6>,<p>,<br/>'), LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NOBLANKS);

• this doesn’t break the page but still strips the BRs. Both <br /> and <br/> behave the same (ie still getting removed).

Update 3:

Following suggestions to simplify the code, I’ve tried the below without any improvement:

$content = get_the_content();
$dom = new DOMDocument(); 
$dom->loadHTML(
    strip_tags($content, '<img><br><div><table><thead><tbody><tfoot><tr><th><td><ul><ol><li><strong><em><h3><h4><h5><h6><p>'),
    LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD | LIBXML_PARSEHUGE | LIBXML_COMPACT | LIBXML_NOBLANKS
);
$html = $dom->saveHTML();
$html = str_replace('<br>', "<br>n", $html); // if you want newlines
echo $html;

Update 4:

As per request, this is what a typical post contains

<br /><p><br /></p><p></p><p></p><p><br /></p><br /><p><div><div><div id="294794216367" data-previewurl="//img.alicdn.com/imgextra/i1/6000000000970/O1CN01xXGd7M1J2Iq5QnJhY_!!6000000000970-0-tbvideo.jpg"></div></div></div></p><br /><p><br /></p><p><br /></p><div><p style="font-family:OpenSans;font-size:20px;font-weight:900;line-height:28px;margin-bottom:12px">We Support Drop Shipping!</p></div><div><p style="font-family:OpenSans;font-size:20px;font-weight:900;line-height:28px;margin-bottom:12px">VRG Pro+：</p><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Note: In order to give you 100% protection of your purchasing glasses ,we will update the shipping into air filled column bag pack like the photo.</p></div><div><img src="//ae01.alicdn.com/kf/H81b56447280d441c914cb64de1c17080Q.jpg" /></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">If you need the item with Retail Box, you can choose the "Glasses add Box" or "add Remote add Box ", and we will send you with the retail box like this photo :</p></div><div><img src="//ae01.alicdn.com/kf/He7c0b55eee974cbdbc16b4d5995034fds.jpg" /></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Features:<br />1. with A Large Headset: The VR glasses with a large headset provides a great experience. The sound quality is strong and stable, the large screen frame is detachable, both large and small screen phones are available (maximum support 7 inches screen phone).<br />2. Full-screen Visual Experience: The maximum image effect and overall experience enable you to enjoy wonderful movies as if you were sitting in front of the theater screen. There is no black-box effect when watching movies.<br />3. Enjoy the Visual Feast: There are independent adjusters for pupil and 0-800° myopia adjustment, so as to provide users with the best visual field. When wearing the goggles, 0-800° myopia users do not need to wear another pair of glasses.<br />4. High Transmittance Optical Lens: The blue-coated lenses can effectively prevent the influence of blue light, stray light and aura, thus ensuring a clearer 120° wide-angle field of view and better immersion.<br />5. Suitable for 5-7 Inch Smartphones: This pair of visual reality goggles is suitable for 5-7 inch IOS and for Android phones. Easily enjoy the perfect screen time.<br /><br />Specifications:<br />Name: VR glasses<br />Type: virtual reality glasses<br />Model: for VRGPRO+<br />Lens type: blue coated lens<br />Lens diameter: about 42mm/1.65in<br />Viewing angle: 120°<br />Myopia adjustment: 0-800°<br />Pupil adjustment: about 60-75mm/2.36-2.95in<br />Material: ABS<br />Compatible platforms: for IOS, for Android<br />Suitable for: 5-7 inch smart phone<br />Plug type: direct insertion<br />Wearing style: head-mounted<br />Headphones: built-in headphones<br />Size: about 19x10x11cm/7.48*3.94*4.33in<br /><br />Packing List:<br />1 x VR Glasses<br />1 x Lens Cloth<br />1 x User Manual<br /><br /><br />Headset Theater Version<br />VRGPRO+<br />New breakthrough in 2020<br />Cinematic audiovisual experience</p></div><div><img src="//ae01.alicdn.com/kf/Hf9376516a5894c93812c3ff2162b1272x.jpg" /></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">8 reasons to choose us<br />① Switch between phones<br />② Large speaker unit<br />③ Compatible with 5 to 7 inches smart phones<br />④ 120-degree FOV (wide angle)<br />⑤ VR glasses with full-screen vision<br />⑥ Adjustable interpupillary distance<br />⑦ Suitable for 0-800 degrees myopia<br />⑧ Blue light filter lenses</p><div><img src="//ae01.alicdn.com/kf/Hea09a6ed8b0e49508f761872ab00cef83.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Enjoy 3D films on your phone<br />Immersive visual and auditory experience</p><div><img src="//ae01.alicdn.com/kf/H8048c972841944acbcc43334d3e5febeI.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Big screen = more fun<br />Are you still buying a regular VR?<br />Or you bought a new phone only to find that it is not compatible with your VR?<br /> <br />Old VR glasses are not made for new phones.<br />Adopting the design for easy switch between small and large screens, it allows you to freely change between phones with different screen sizes.</p><div><img src="//ae01.alicdn.com/kf/Hc2b2ab25033c4b4cb1dde08cbf9440b2S.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Unfold the new era of 5G audio and video with new VR glasses (Compatible with both new and old phons)</p><div><img src="//ae01.alicdn.com/kf/H7d95a8402380426fadcbc6b86c24e7fe5.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Small or big, switch as you like.<br />Adopting the design for easy switch between small and large screens, it allows you to freely change between phones with different screen sizes.</p><div><img src="//ae01.alicdn.com/kf/H55a7104b05724c9881af8f8774995d6ax.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">VR glasses with full-screen vision <br />Full screen, no borders</p><div><img src="//ae01.alicdn.com/kf/H122113e8c26842e2b4b4d71fa056470fq.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Enjoy a shocking audio-visual feast<br />10 years of professional <br />research on speaker sound<br />quality to make products better<br />Incredibly immersive experience</p><div><img src="//ae01.alicdn.com/kf/H1c8e6e2541554065b484c1eaf7b85aa59.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">VR GLASSES+<br />HEADPHONES AIO<br />Hi-Fi Headphones<br /> <br />Independent control buttons<br />As is the case with most headphones, this headset may not match all<br />video/audio apps and their keypad functions<br />Sorry for the inconvenience brought <br />(ios devices accept only original Apple accessories in terms of volume control).</p><div><img src="//ae01.alicdn.com/kf/H9b92f76bfbc74bada6a5c292f5af05f9v.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Hi-Fi Headphones<br />Enjoy a shocking audio-visual feast</p><div><img src="//ae01.alicdn.com/kf/H4625ad2de05a4acca46bbcf211f64cf8S.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Easily embark on your 3D journey<br />1. Open the mobile phone APP;<br />2. Put the mobile phone into the glasses;<br />3. Insert the headphone plug into the mobile phone</p><div><img src="//ae01.alicdn.com/kf/H3d89e020199c484d9450526024f872b5W.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Compatible with 5 to 7 inches smart phones<br /> <br />Suitable for Android / iPhone<br />Adopting the design for easy switch between small and large screens, it allows you to freely change between phones with different screen sizes.</p><div><img src="//ae01.alicdn.com/kf/Hce79932eb4634fa8944fb709e8b7dd48C.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">3D effect + immersion</p><div><img src="//ae01.alicdn.com/kf/H77d6fc0f9276410bb1e74cb6ba175f9d4.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Friendly to myopia users within 800 degrees<br />No need to wear myopia glasses (Adjustment of the VR glasses will do.)</p><div><img src="//ae01.alicdn.com/kf/H33133a5d6dba44f3b00059f04246d5c3H.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Interpupillary distance adjuster</p><div><img src="//ae01.alicdn.com/kf/Hb97d5d335808435d83bde4e2d376ef66K.jpg" /></div></div><div><p style="font-family:OpenSans;font-size:14px;font-weight:300;line-height:20px;margin-bottom:12px">Blue light filter lenses</p></div><div><img src="//ae01.alicdn.com/kf/Hcd4ae33bc27347b08af5b3b75810693eE.jpg" /><img src="//ae01.alicdn.com/kf/H940cdee1dfce4fdeb50311df2b729c3fR.jpg" /><img src="//ae01.alicdn.com/kf/H9bccd755eb7f4102917d0c49654c455cX.jpg" /></div><div><p style="font-family:OpenSans;font-size:20px;font-weight:900;line-height:28px;margin-bottom:12px">VRG Pro：</p><div><img src="//ae01.alicdn.com/kf/Se2b847e866dd42cfbc29604f4f192f96W.jpg" /><img src="//ae01.alicdn.com/kf/S9cb212bb714a474eb7a20eb862cd8d007.jpeg" /><img 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