Why isn't my product page timer showing on some products? (Essential Countdown Timer app)

A product page timer only shows when every check below passes. Go through them in order.

• The timer is published, and its schedule allows it to show now. Check the start and end dates and the recurring days.
• The placement is Product page.
• The product matches the rule. For All products, the product must not be in the excluded list. For Specific products, the product must be selected. For Specific collections, the product must be in one of the selected collections. For Product tags, the product must have one of the tags. Tag matching is not case-sensitive.
• The app embed is on. Go to Online Store → Themes → Customize → App embeds, turn on Countdown Timer, and select Save.
• If you use Custom position, the timer does not add itself. Add the Countdown Timer app block to the product template with the correct Timer ID.

Good to know

Changes can take a short while to reach the storefront. Check the live product page, not only the theme editor preview.