Previously if upload had missing width and height we would calculate
on first use BUT we (me) forgot to save this to the database
This was particularly bad on home page cause category images (when old)
miss dimensions.
This allows fidelity in controlling excerpt (text that shows up when you pin a topic or link to it externally):
```
I am some text
[excerpt]
This is some **custom** markdown that should be the excerpt
[/excerpt]
More text
```
Previous solution relied on DIVs, unfortunately DIVs do not play well,
by design with mixing markdown unless you have a preceding newline eg:
```
<div class='hello'>
this will be treated properly as markdown
</div>
```
This extra newline is not desirable.
I am also considering adding
```
[div class=excerpt]
[/div]
```
This would offer lots of flexibility to themes and plugins that do not want the extra annoying newline.
As per the documentation for KEYS
```
Warning: consider KEYS as a command that should only be used in production environments with extreme care. It may ruin performance when it is executed against large databases. This command is intended for debugging and special operations, such as changing your keyspace layout.
```
Instead SCAN
```
Since these commands allow for incremental iteration, returning only a small number of elements per call, they can be used in production without the downside of commands like KEYS or SMEMBERS that may block the server for a long time (even several seconds) when called against big collections of keys or elements.
```
This generates a 10x10 PNG thumbnail for each lightboxed image.
If Image Lazy Loading is enabled (IntersectionObserver API) then
we'll load the low res version when offscreen. As the image scrolls
in we'll swap it for the high res version.
We use a WeakMap to track the old image attributes. It's much less
memory than storing them as `data-*` attributes and swapping them
back and forth all the time.
This validation makes sure that the s3_upload_bucket and the
s3_backup_bucket have different values. The backup bucket is
allowed to be a subfolder of the upload bucket. The other way
around is forbidden because the backup system searches by
prefix and would return all files stored within the backup
bucket and its subfolders.
* Dashboard doesn't timeout anymore when Amazon S3 is used for backups
* Storage stats are now a proper report with the same caching rules
* Changing the backup_location, s3_backup_bucket or creating and deleting backups removes the report from the cache
* It shows the number of backups and the backup location
* It shows the used space for the correct backup location instead of always showing used space on local storage
* It shows the date of the last backup as relative date
`SiteSerializer#is_readonly` is cached for an anonymous user so we have
to clear the cache when disabling readonly mode. Otherwise, the site may
appear to be in readonly mode for an extended period of time.