back button doesn't close certain views

**Describe the bug**
Most of the app has consistent behavior with the back button: close the current view and return to the previous view where you had left off. There are a few places in the app that I've noticed it does not behave the same: compose new post, compose reply post, and account "preview".
- Which site: dev.phanpy.social
- Which instance: infosec.exchange

**To Reproduce**
Steps to reproduce the behavior:
1. On your home feed, click on a post.
2. Click on "reply to post".
3. Click the browser back button.
4. Notice the reply to post screen is still active, and the background is now on your home feed instead of viewing the post being replied to.
5. This also happens when composing a new post, and also when you view someone's account details by clicking on their avatar.

**Expected behavior**
The "reply to post" view will close and return to the post being replied to.

**Desktop (please complete the following information):**
- OS: Windows
- Browser: Firefox
- Version: 115

**Smartphone (please complete the following information):**
- Device: Samsung S23
- OS: Android
- Browser: Chrome PWA
- Version: 115

**Additional context**
This behavior is present in mobile chrome PWA and also Firefox on my windows desktop.

Reproduce the browser-back flow from a home-feed post into reply composition, then check the same behavior for new-post composition and account preview. Trace how these views are opened and closed during navigation. Done means back closes the active view and restores the post or previous view, consistently on the reported desktop and mobile PWA flows.

Written by the indexing model from the issue text.