Different Cell rendering in tag

Hello,
we're testing IW16.1.9 in D13.
Comparing it to 16.0.8 with D12, we noticed thad &ttd&t elements rendered from DBGrid are using a random CSS (if not assigned by application), while "style=white-space nowrap" is not present anymore.
old:&ttd style="white-space: nowrap; "&t
new:&ttd class="iw_1575348624"&t

Also, if I specify a Cell[x,y].Widht:='99%', it was rendered in the style tag:
&ttd style="white-space: nowrap; width: 99%; "&t
Now, it is replaced by a iw class, e.g. &ttd class="iw_3764614034"&t that lack the width property.

Because of this, sometime the page has some differences; we can correct it with a new css, but I was wonder if there is some property to maintain the old behavior because we have hunderes of dbgrid to check.

Thanks,
best regards
Alberto