flex item overflows container due to long word even after using word-wrap

Instead of word-wrap:break-word use word-break:break-all

CSS

.child1{
  background-color:mistyrose;
  padding:1em;
  word-break:break-all;
}
.child2{
  background-color:powderblue;
  padding:.5em;
  max-width:500px;
  word-break:break-all;
}
.child3{
  background-color:powderblue;
  padding:.5em;
  word-break:break-all;

}

here is the working fiddle link http://jsfiddle.net/yudi/vbj10x4k/3/

Instead of setting a max-width for your flex item, use a min-width declaration.

By default, if no min-width is set, the item's content min-width is assumed and the flex item's width will never be smaller. By setting a min-width of e.g. 40%, the item will shrink to at most 40% of the flex parent.

.child2, .child3 {
  min-width: 40%;
}

.parent{
  width:100%;
  display:flex;
  flex-direction:row;
  flex-wrap:nowrap;
  padding:1em;
  background-color:red;
  box-sizing:border-box;
}
.child1{
  background-color:mistyrose;
  padding:1em;
}
.child2{
  background-color:powderblue;
  padding:.5em;
  word-wrap: break-word;
  overflow-wrap: break-word;
  min-width: 40%;
}
.child3{
  background-color:lightyellow;
  padding:.5em;
  word-wrap: break-word;
  overflow-wrap: break-word;
  min-width: 40%;
}

<div class="parent">
  <div class="child1">
    question
  </div>
  <div class="child2">
   somethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomethingsomething

  </div>
  <div class="child3">
    Works well with long URLs: <a href="#"> https://thisisadamnlongurlcontainingneitherhyphensoradditionalperiods.com</a>
  </div>
</div>

See the code snippet above or the external demo: http://jsfiddle.net/vbj10x4k/5/

I am using a combination like this and it works for me on Chrome, Safari, and Firefox.

.myOverflowableText {
  word-break: break-word; /* Chrome, Safari */
  overflow-wrap: anywhere; /* Firefox */
}

This site says word-break is supported on Chrome & Safari https://caniuse.com/#feat=word-break.

But I found that Firefox's solution should be overflow-wrap: anywhere on this site: https://developer.mozilla.org/en-US/docs/Web/CSS/overflow-wrap

I'm not sure about IE yet... Maybe word-wrap: break-word; works on IE?

My goal is this:

Hello this is some |
text. I am writing |
some text.         |
Especially long    |
words go to the    |
next line like     |
this. This is a    |
veryveryveryveryve |
ryveryverylongword |
.                  |