Why in firefox and explorer there is no slider to scroll?

There is a div with overflow: scroll; but it only works in Chrome and in other browsers it works like overflow:hodden; though scroll is displayed, the styles themselves are working but the slider is not..

.DivToScroll {
 border-radius: 0px 10px 4px 0px;
 font-weight: bold;
 padding: 10px 7px 5px;

.DivWithScroll {
 overflow: scroll;
 overflow-x: hidden;

::-webkit-scrollbar {
 width: 12px;

::-webkit-scrollbar-track {
 -webkit-box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.3);
 border-radius: 10px;
 background-color: #555555;

::-webkit-scrollbar-thumb {
 border-radius: 10px;
 background-color: rgba(0,0,0,0.6);
 -webkit-box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.5);


and as for moz/ms
March 12th 20 at 08:09
1 answer
March 12th 20 at 08:11
Because these browsers work on other engines. Add to them the settings in css:
Engine: Trident
CSS-prefix: -ms
The Engine EdgeHTML
CSS-prefix: -ms
Engine: Gecko
CSS-prefix: -moz
Engine: Presto → Blink 1
CSS-prefix: -o (Presto) and-webkit (Blink)
Engine: WebKit
CSS-prefix: -webkit
Engine: WebKit → Blink 2
CSS-prefix: -webkit

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