In markdown editor, internal links are prefixed with a joplin logo. It would be nice to have that for the richtext editor, too. It makes distinguishing weblinks and internal links easier.
For now I'm using a hacky userstyle.css to achieve this behavior:
#tinymce a[data-resource-id]::before {
position: absolute;
width: 1em;
height: 1em;
top: 0.05em;
left: -1.2em;
/* https://github.com/laurent22/joplin/blob/6ea40c9895a74449c81977807ac9a28b955d90e9/packages/renderer/noteStyle.ts#L181 */
content: url("data:image/svg+xml;utf8,<svg viewBox='0 0 1536 1792' xmlns='http://www.w3.org/2000/svg'><path d='M373.834 128C168.227 128 0 296.223 0 501.834v788.336C0 1495.778 168.227 1664 373.834 1664h788.336c205.608 0 373.83-168.222 373.83-373.83V501.834C1536 296.224 1367.778 128 1162.17 128zm397.222 205.431h417.424a7.132 7.132 0 0 1 7.132 7.133v132.552c0 4.461-3.619 8.073-8.077 8.073h-57.23c-24.168 0-43.768 19.338-44.284 43.374v2.377h-.017v136.191h-.053l-.466 509.375c-5.02 77.667-39.222 149.056-96.324 201.046-60.28 54.834-141.948 85.017-229.962 85.017-12.45 0-25.208-.61-37.907-1.785-92.157-8.682-181.494-48.601-251.662-112.438-71.99-65.517-117.147-150.03-127.164-238-11.226-98.763 23.42-192.783 95.045-257.937 81.99-74.637 198.185-101.768 316.613-75.704 5.574 1.227 9.55 6.282 9.55 11.997v199.52c-.199 2.625-1.481 6.599-8.183 2.896-.663-.365-1.194-.511-1.653-.531-21.987-10.587-45.159-17.57-68.559-19.916-.38-.04-.757-.124-1.138-.163-.537-.048-1.034-.033-1.556-.075-4.13-.354-8.183-.517-12.203-.58-.87-.011-1.771-.127-2.641-.127-.486 0-.951.05-1.437.057-1.464.011-2.886.115-4.33.163-2.76.102-5.497.211-8.182.448-.273.024-.547.07-.835.097-25.509 2.4-47.864 11.104-65.012 25.47-.954.802-1.974 1.53-2.9 2.36a1.34 1.34 0 0 1-.168.146c-23.96 21.8-34.881 53.872-30.726 90.316 4.62 40.737 26.94 81.156 62.841 113.823 35.908 32.67 80.335 52.977 125.113 57.186 35.118 3.36 66.547-3.919 89.899-20.461a97.255 97.255 0 0 0 9.365-7.501c2.925-2.661 5.569-5.5 8.086-8.416.3-.348.672-.673.975-1.024 8.253-9.864 14.222-21.067 17.996-33.148.639-2.034 1.051-4.148 1.564-6.227.381-1.563.81-3.106 1.112-4.693.555-2.784.923-5.632 1.253-8.49.086-.709.183-1.414.237-2.128.492-4.893.693-9.858.55-14.91h.013V521.623c-2.01-22.626-20.78-40.434-43.928-40.434h-57.23a8.071 8.071 0 0 1-8.077-8.073V340.564a7.132 7.132 0 0 1 7.136-7.133z'/></svg>");
}
#tinymce a[data-resource-id] {
position: relative;
left: 1.2em;
}
For a correct implementation it might be sufficient to add a <span class="resource-icon fa-joplin"></span> at the corresponding position when rendering.