White screen for 3-5 seconds after first scroll (Blocksy (Gadgets theme)

Hello,

After installing you pligin, I’m facing a critical performance issue on iOS.

Symptoms:

1. The website shows a white screen for 3-5 seconds before rendering after scroll (after frist screen). Once loaded, scrolling causes the screen to go white again.
2. The entire phone UI becomes laggy/unresponsive while the site is loading.

Important Contrast:

• The website works perfectly on older Android devices. This confirms the issue is NOT related to server performance, image sizes, or general site weight.
• It is specifically a conflict with iOS/Safari/Chrome rendering engine (WebKit) in the latest theme build.

What I’ve tested:

• I disabled ALL custom CSS and PHP snippets — the issue persists even on a clean theme setup.
• The issue only appeared exactly on iOS.

Environment:

• Theme: Blocksy (latest version)
• Device: iPhone 14 Plus / iPhone 15 / Realme 6
• OS: iOS 18+

It seems like a JS execution or CSS Layer Compositing conflict. Please investigate.

So, the problem appears due to the WPForms Lite (plugin).

• I deleted all my CSS and disabled all plugins to find the problem. Once I disable WPForms Lite no delay at all.

I tried below CSS. It helps little bit (now delay is not 5 but 3 seconds after scroll) but, this is not a solution still.

@supports (-webkit-touch-callout: none) {
/* Фиксируем фон для всего документа, чтобы исключить “прозрачные” дыры / html, body { background-color: #ffffff !important; -webkit-overflow-scrolling: touch; / Плавный скролл */
}

/* Максимальная стабилизация для контейнера формы */
.wpforms-container, .wpforms-form {
    backface-visibility: hidden !important;
    -webkit-backface-visibility: hidden !important;
    transform: translate3d(0, 0, 0) !important; /* translate3d мощнее translateZ */
    -webkit-transform: translate3d(0, 0, 0) !important;

    /* Сообщаем браузеру заранее, что элемент будет меняться */
    will-change: transform; 

    /* Убираем возможные конфликты с тенями или свечением */
    -webkit-perspective: 1000;
    perspective: 1000;
}

After my research I understood that this is a known issue or a misconfiguration. More over, the problem appeared after one of you last plugin update.

• I disabled pre-loaders and cache so you can check.

The page I need help with: [log in to see the link]