Use this code under Countdown Timer Plugin code (in Footer Injection)
<!-- Countdown Timer tweak Days to Day - @tuanphan -->
<script>
setInterval(()=>{const timers=document.querySelectorAll('[data-wm-plugin="countdown-timer"]');timers.forEach(timer=>{const dayDigit=timer.querySelector('.day-digit');const dayText=timer.querySelector('.days .text');const hourDigit=timer.querySelector('.hour-digit');const hourText=timer.querySelector('.hours .text');const minuteDigit=timer.querySelector('.minute-digit');const minuteText=timer.querySelector('.minutes .text');const secondDigit=timer.querySelector('.second-digit');const secondText=timer.querySelector('.seconds .text');if(dayDigit&&dayText){const dayValue=parseInt(dayDigit.textContent);const dayTextElement=dayText.querySelector('h4, h1, h2, h3, h5, h6, p');if(dayTextElement){dayTextElement.textContent=dayValue===1?'Day':'Days'}}
if(hourDigit&&hourText){const hourValue=parseInt(hourDigit.textContent);const hourTextElement=hourText.querySelector('h4, h1, h2, h3, h5, h6, p');if(hourTextElement){hourTextElement.textContent=hourValue===1?'Hour':'Hours'}}
if(minuteDigit&&minuteText){const minuteValue=parseInt(minuteDigit.textContent);const minuteTextElement=minuteText.querySelector('h4, h1, h2, h3, h5, h6, p');if(minuteTextElement){minuteTextElement.textContent=minuteValue===1?'Minute':'Minutes'}}
if(secondDigit&&secondText){const secondValue=parseInt(secondDigit.textContent);const secondTextElement=secondText.querySelector('h4, h1, h2, h3, h5, h6, p');if(secondTextElement){secondTextElement.textContent=secondValue===1?'Second':'Seconds'}}})},1000)
</script>