Browsers on iOS are ignoring the width property for iframes,
this resulted in iframes beeing rendered too wide and prevented
scrolling on the horizontal axis.

Resolves: #83841
Releases: master, 8.7
Change-Id: I825d6f911959fdb588f1f164f0ec4bbbf5c067c0
Reviewed-on: https://review.typo3.org/55649


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Tested-by: Mathias Schreiber <mathias.schreiber@typo3.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Benjamin Kott <benjamin.kott@outlook.com>
Tested-by: Benjamin Kott <benjamin.kott@outlook.com>