A work-around for spoiler cuts on Dreamwidth:

[rahirah]

Here.

1. Go to Customize Your Journal Style.
2. Scroll down to Customize Journal Theme.
3. Click on Custom CSS.
4. In the box labeled "Use embedded CSS." paste the following:

/* MOCK SPOILER CUTS */
div[tabindex] {display: inline;}
div[tabindex]>b~div {display: none;}
div[tabindex]>b {color: #00f; text-decoration: underline; cursor: pointer;}
div[tabindex]>b::before {content: "[";}
div[tabindex]>b::after {content: "]";}

div[tabindex]:focus>b {display: none;}
div[tabindex]:focus>b~div {display: inline;}
div[tabindex]:focus {outline: none;}

5. Save changes.
6. To use spoiler cuts in your journal, use the following code:

spoiler title
Some spoilery content.

Full explanation at the link; it won't work in absolutely every instance, but it will in most cases.

When used in a post, it looks like this:

This here is a spoiler
Rocks fall, everybody dies.
Rants Talk to me