Changes since v1.6.19:

Improved the Smart Translate popup UI.
Removed the informational privacy hint from the translation popup.
Removed text-to-speech playback for the Persian translated text.
Added a Copy button for the original selected text next to the existing audio playback button.
Added visual feedback after successfully copying the original selected text.
Preserved the non-modal translation popup behavior, allowing normal interaction, clicking, right-clicking, and text selection on the underlying webpage.
Fixed bundled Persian font loading in Chrome/Chromium.
Chromium now uses the standard extension @font-face loading approach with web-accessible font resources instead of JavaScript FontFace.load(), preventing font-loading DOMException errors.
Firefox font loading remains unchanged and continues to use its existing working implementation.
Verified bundled WOFF2 font files and added regression coverage for browser-specific font loading.
General stability and regression-test improvements.