To stop WordPress from generating PDF preview images for new uploads, add a filter that returns no fallback image sizes: add_filter( 'fallback_intermediate_image_sizes', '__return_empty_array' ); WordPress uses this filter in its PDF preview-generation path. It applies to fallback sizes for non-image files generally, so check for other site code that relies on those sizes before enabling it site-wide.
What the setting changes
Since WordPress 4.7, core can create a JPEG preview of the first page of an uploaded PDF. The preview can appear in places such as the Media screen, Gallery, Attachment Details, and PDF attachment pages, as described in the WordPress 4.7 PDF support announcement.
During attachment metadata generation, core checks fallback image sizes for non-image files. For PDFs, it can load the document through an image editor, save a preview JPEG with a -pdf.jpg filename, and generate configured sub-sizes. Returning an empty array from the filter prevents those fallback sizes from being supplied for this process. It does not disable PDF uploads or change how a browser renders a PDF.
Add the filter
- Choose where the change will live. Put the snippet in a small site plugin or a code-snippet manager rather than a theme file, so a theme update does not remove the setting.
- Add this PHP code:
add_filter( 'fallback_intermediate_image_sizes', '__return_empty_array' ); - Check the effect safely. If the site has custom media-processing code, try a new PDF upload on staging first, or take a backup before changing the live site.
The WordPress Developer Resources function reference for wp_generate_attachment_metadata() documents the fallback-size filter and the PDF metadata-generation path. The WordPress 4.7 announcement also identifies this filter as the control for modifying or disabling PDF preview sizes.
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#1 Best Overall
- Ergonomic Posture Correction: Designed to elevate your laptop to the perfect eye level, this adjustable laptop stand significantly reduces neck, shoulder, and spinal fatigue. Transform your desk into a healthier workstation, ideal for long hours of typing, Zoom meetings, or gaming.
- Unshakable Dual-Rod Stability: Unlike single-hinge models, our stand features a highly engineered dual-support rod mechanism. It perfectly distributes weight to ensure a 100% wobble-free typing experience, safely supporting heavy-duty devices up to 22 lbs (10kg).
- Advanced Thermal Cooling Panel: Maximize your device's performance. The unique geometric heat-vent design on the upper panel provides superior airflow compared to standard solid stands. This continuous heat dissipation prevents your laptop from thermal throttling and hardware damage during intensive tasks.
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Understand the filter’s scope
fallback_intermediate_image_sizes is not documented as a PDF-only hook: it concerns fallback image sizes for non-image MIME types. Returning an empty array globally may therefore affect other non-image attachment processing that uses those fallback sizes. The official sources explain the broad filter and PDF path, but do not provide an official PDF-only conditional example. If your site depends on fallback sizes for other non-image media, review that code before applying the global snippet.
What happens to previews already created?
The filter controls generation during metadata processing; the official documentation does not say that adding it removes JPEG previews or metadata created earlier. If you also want to remove old derivatives, treat that as a separate maintenance task: back up the site first, then handle the existing files and attachment metadata deliberately. Do not assume the snippet performs that cleanup.
Rank #2
- Broad Compatibility: Besign LS03 Laptop Mount is compatible with all laptops from 10''-15.6'', such as Air 13, Pro 13 / 15 / 2018 / 2017 / 2016, Lenovo ThinkPad, Dell, HP, ASUS, Chromebook, and other notebooks.
- Ergonomic Design: This LS03 Laptop Stand could elevate your laptop by 6’’ to a perfect viewing level, help you improve your posture and reduce neck and shoulder pain. This laptop stand is super easy to detach and assemble.
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- Keep Laptop Cool: the open aluminum design provides good ventilation and airflow to prevent your laptop from overheating. It folds flat if you need to store it, create extra space on your desk and keep your desk clean and organized.
- Easy to Use: thanks to the detachable design, you could assemble it very easily it 3 steps.
Why a PDF preview may not appear anyway
Preview generation depends on the available image-editor and PDF-processing support. The WordPress 4.7 announcement describes support involving WP_Image_Editor_Imagick, Imagick, ImageMagick, and Ghostscript. If support is unavailable or generation fails, core can continue without adding preview image metadata. That is different from disabling future generation with the filter.
Quick Recap
Best Value
- ✅【Adjustable & Ergonomic】：This laptop stand can be adjusted to a comfortable height and angle according to your actual needs, letting you fix posture and reduce your neck fatigue, back pain and eye strain. Very comfortable for working in home, office and outdoor.
- ✅【Sturdy & Protective】 ：Made of sturdy metal, it can support up to 17.6 lbs (8kg) weight on top; With 2 rubber mats on the hook and anti-skid silicone pads on top & bottom, it can secure your laptop in place and maximum protect your device from scratches and sliding. Moreover, smooth edges will never hurt your hands.
- ✅【Heat Dissipation】 ：The top of the laptop stand is designed with multiple ventilation holes. The open design offers greater ventilation and more airflow to cool your laptop during operation other than it just lays flat on the table.
- ✅【Portable & Foldable】：The foldable design allows you to easily slip it in your backpack. Ideal for people who travel for business a lot.
- ✅【Broad Compatibility】：Our laptop holder is compatible with all laptops from 10-17.3 inches, such as MacBook Air/ Pro, Google Pixelbook, Dell XPS, HP, ASUS, Lenovo ThinkPad, Acer, Chromebook and Microsoft Surface, etc.Be your ideal companion in Home, Office & Outdoor.
Rank #4
- 【Adjustable & Ergonomic】：This laptop stand can be adjusted to a comfortable height and angle according to your actual needs, letting you fix posture and reduce your neck fatigue, back pain and eye strain. Very comfortable for working in home, office and outdoor.
- 【Sturdy & Protective】 ：Made of sturdy metal, it can support up to 17.6 lbs (8kg) weight on top; With 2 rubber mats on the hook and anti-skid silicone pads on top & bottom, it can secure your laptop in place and maximum protect your device from scratches and sliding. Moreover, smooth edges will never hurt your hands.
- 【Heat Dissipation】 ：The top of the laptop stand is designed with multiple ventilation holes. The open design offers greater ventilation and more airflow to cool your laptop during operation other than it just lays flat on the table.
- 【Portable & Foldable】：The foldable design allows you to easily slip it in your backpack. Ideal for people who travel for business a lot.
- 【Broad Compatibility】：Our desktop book stand is compatible with all laptops from 10-15.6 inches, such as MacBook Air/ Pro, Google Pixelbook, Dell XPS, HP, ASUS, Lenovo ThinkPad, Acer, Chromebook and Microsoft Surface, etc.Be your ideal companion in Home, Office & Outdoor.
Rank #3
- ✔️[Foldabe & Protable] - Foldable laptop stand for desk & Protable computer stand, It combines the advantages of market brackets, convenient travel laptop stand. Easy to use. Suitable for working at home, office and outdoor, improve comfort.
- ✔️[360°Rotation] - The computer stand with 360° rotating base, 360° rotation connected with the base is more flexible, the computer stand allows you to rotate the laptop to any angle.
- ✔️[Stable & Durable] - The Computer stand is made of one-piece fiber metal material, which is more durable and stable than ordinary aluminum alloy computer stands. The upgraded rotating base makes the stand performance more stable, and the non-slip silicone protects the laptop from sliding.Only supports laptops up to 16 inches.
- ✔️[Ergonmic Desing] - You can freely adjust the height and angle of the laptop stand to keep it at eye level, which helps to reduce the pressure on your body while working. Whether sitting or standing, there is a comfortable angle.
- ✔️[Wide Compatibility] - Our laptop stand is compatible with all laptops from 10-16 inches, such as MacBook Air/Pro, Google PixelBook, Dell XPS, HP, ASUS, Lenovo ThinkPad, Acer, Chromebook and Microsoft Surface, etc. It is an ideal companion for computer workers.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
