Gallery as Gutenberg “Gallery” block
Please note, that Gutenberg had a bug which caused the images to be displayed smaller as they really are (also see https://github.com/WordPress/gutenberg/issues/13851). If you already created a gallery you may need to remove the images and add them again. You also need to add an additional CSS rule to be able to click the images inside the caption:
figcaption { pointer-events: none; }
Gutenberg single image
Images with special file names or special characters in the caption
These images use non-ASCII characters in the file name:
“Piëch-Mark-Zero-6.jpg”:
“umlaut-äöü.jpg”:
This image contains emojis like 😊:
Image with alt attribute and EXIF data but no other caption:
Images with the characters ” or ‘ in the caption
The “machine” (alternative text)
“Logitech K270” with ‘unifying’ receiver (description)
Image without any caption:
Image with a very long text as caption: