XP users have to upgrade to TV 14 in 2019. My computer fulfills all requirements listed for TV14 (Windows XP SP3, 32 bit, Internet Explorer 8). However, since some applications (virus protection, IP cameras) don't install because there is an Intel Pentium III core which doesn't "understand" some commands of more recent instruction sets, I WOULD LIKE TO KNOW IF TeamViewer 14 WILL ALSO WORK WITH THE Pentium III (32 bit) instruction set or, if not, if TV can be adapted somehow (by you or by me) to work also on a Pentium III using XP SP3 (32 bit) and IE 8. --- By the way, I do not understand why IE 8 is required since I am working with Firefox 52.9.0 (most recent working with XP) and some adaptions (activated Adobe Primetime CDM, Java 8u92) in order to be able to see also HTML5-HDvideo (webcams). I don't use IE 8 at all.
I don't know with which assembly optimisations Team Viewer has been compiled, but it should be possible to compile it disabling any assembly optimisation. As a matter of fact, nowadays, companies compile targeting at least SSE2 'cause it's supposed to be the bare minimum for a modern CPU. Anyway, since Team Viewer is closed source (and disassemblers give only a broad view of the code underneath), there's nothing you can do other than waiting for their official reply.
Oh and by the way, Firefox 52.9.1 is the latest version for XP, not 52.9.0.