Kibana doesn't seem to honor default 25MB max payload

[n0othing]

Kibana version: 7.4.1

Elasticsearch version: 7.4.1

Server OS version: n/a

Browser version: Chrome Version 77.0.3865.120 (Official Build) (64-bit)

Browser OS version: macOS Mojave 10.14.6 (18G103)

Original install method (e.g. download page, yum, from source, etc.): tarballs

Describe the bug:

#31974 increased server.maxPayloadBytes to 26214400 (25MB), but I'm unable to save a Markdown Visualization w/ a >1MB payload unless I explicitly set server.maxPayloadBytes: 26214400 in the kibana.yml

Steps to reproduce:

1. base64 encode a >1MB image (here's one!)
2. Create a Markdown Visualization and copy/paste the linked base64 image (your browser will likely hang a bit as you try to apply it).
3. Try to save the visual.

Expected behavior:

The visual's payload is < 25MB, so it should save successfully.

Screenshots (if relevant):

Errors in browser console (if relevant):

{"statusCode":413,"error":"Request Entity Too Large","message":"Payload content length greater than maximum allowed: 1048576"}

Any additional context:

Adding server.maxPayloadBytes: 26214400 to the kibana.yml will allow the above visual to successfully save.

[kobelb]

Hey @n0othing, #31974 only bumped up this limit for a specific route which isn't used to save markdown visualizations.

[n0othing]

Ah, I see! I saw #48206 and thought it applied to all routes. Will close.