HEIC/HEIF Image Support and User Guidance

Start by locating TinyMCE's image upload and image-rendering entry points and checking how browser support is currently handled; the issue names no files or tests. First clarify whether conversion, configuration, or user guidance is intended, then define supported-browser behavior and coverage for the selected approach.

📝 Provide a description of the new feature or improvement

As adoption of Apple devices continues to increase across iOS, iPadOS, and macOS, more users are creating and uploading images in the HEIC/HEIF format. While Safari provides native support for these formats, most other browsers currently do not.

When a user uploads a HEIC image into TinyMCE, the image can appear blank or fail to render entirely in unsupported browsers. This occurs without any warning, validation message, or guidance, leading users to believe the upload has failed or the editor is malfunctioning.

We are requesting improved handling of HEIC/HEIF image formats through one or more of the following approaches:

Automatic conversion of HEIC/HEIF images to a broadly supported format such as JPEG or PNG during upload.
Configuration options allowing developers to explicitly permit, block, or transform HEIC/HEIF uploads.
User-facing validation and guidance that detects unsupported image formats and clearly explains:
Why the image may not be visible.
Which browsers support the format.
Recommended alternatives or conversion options.

🫶 What is the motivation?

Many organisations support a large number of Apple device users. HEIC is the default image format on Apple devices, making this issue increasingly common.

Providing native support or clear user guidance would:

Reduce user confusion and frustration.
Decrease support tickets related to image uploads.
Improve accessibility and cross-browser consistency.
Deliver a more predictable editing experience across platforms.

🔗 What is the consequence of not having this feature?

Without any detection or guidance:

Users can successfully upload an image but see a blank placeholder or missing content.
Users often believe the editor is broken.
Support teams receive avoidable requests for assistance.
Content authors may unknowingly publish content with non-visible images for many users.

As HEIC adoption continues to grow, this issue is likely to become increasingly common.

🚦 How important would you rate the requested feature or improvement?

Critical

If you'd like to see this implemented sooner, add a 👍 reaction to this post.