Strange Code issue

For some inexplicable reason, if I add any working code to any page (except for my 7.0 landing/home page) header code injection and then at some point delete the code,  the page  goes completly white on all desktop browsers that I have. I then have to add some working code back into the header injection and the page restores itself. I don't think this is an SS wide problem. I suspect that there is  some strange interaction with some of my custom css. Any other folks experiencing this?

Can you set up a test page where we can potentially see the issue?

I can try that. One thing you will notice, the SS logo will be on the page, and normally it is not. 

https://myrandomviews.com/lipizanners

Quote

I can try that.

It does show up white here as well, except for the powered by SS icon.

I'll dig in a bit and see what I can see.

Hmm... the body tag is pretty much devoid of content.

My first thought is an error in the source that is causing a DOM rendering issue but I'm not seeing the usual signs of DOM weirdness that can often be seen while examining elements in the inspector.

I've gone to the source for the page and there is more there.

I then used w3.org markup validator to see if it can help point out issues and it seems to have found some. The first one that jumped out was the following.

The following code is missing a closing tag.

<style>
#header a:active{
 text-decoration: underline !important;
}
#header a:hover{
 text-decoration: underline !important;
}
div.folder.active{
 text-decoration: underline !important;
}

I added it in locally and reloaded the page.

Let us know how it goes.

I added your code in advanced header code injection along with the closing tag and it did not restore the page. Is there a way I can load the tag in the proper place?  I added this code in code injection header and it also restored the page: 

<style>sqs-gallery-block-slideshow .sqs-gallery-controls .next,
.sqs-gallery-block-slideshow .sqs-gallery-controls .previous {
  background: none; /*removes the original background behind the arrows*/
}
.sqs-gallery-block-slideshow .sqs-gallery-controls .next::before,
.sqs-gallery-block-slideshow .sqs-gallery-controls .previous::before {
  background: white;
  color: black;
  font-size: 1.1em; /*this changes the size of the arrows*/
  padding: 10px;
  border-radius: 50%; /*remove this is you don't want the background rounded*/
}</style>

51 minutes ago, derricksrandomviews said:

I added your code in advanced header code injection along with the closing tag and it did not restore the page.

I should have been more clear. I did not add the code. I added the missing style close tag to that code because it was missing the close tag.

Is the code I show your custom code or SS default code?

It is custom code I added in settings/advanced/header code injection to add underllines on my Nav bar items:

You found where the problem lies. I deleted the code and the page now works as it should. I would like to have the underline back, and I appear to have done that. I removed the <style> tags and posted the code in Design/Custom CSS as opposed to header injection and all appears to be working now. Thank you Creedon for finding where this bug originated. The code had been in the header injection for a long time, not sure why it broke, and still did not work after adding <style> at the end. 

#header a:active {
 text-decoration: underline !important;
}
#header a:hover {
 text-decoration: underline !important;
}
div.folder.active {
 text-decoration: underline !important;
}