When you open this in Safari on the Desktop (I used 26.1), and start a composition inside the empty `` field.

E.g. use the dead key ^ and then press a).

Notice how the original editable-field `
` gets destroyed (the blue dashed border disappears).

Now change the `
` to a `
` and try again. Now it works. as expected. In Chrome/Firefox, this problem does not occur.