Rule: upgrade to v0.33.0: error in thanos url template

[ahurtaud]

Thanos, Prometheus and Golang version used:
thanos v0.33.0

What happened:
Upgrading from v0.32 to v0.33.0, the thanos url advertised by our ruler cannot be opened back in thanos query anymore.
I think this is due to #6308

What you expected to happen:
Thanos urls to be clickable as before

How to reproduce it (as minimally and precisely as possible):
We have not changed anything so it is using the default:
--alert.query-template="/graph?g0.expr={{.Expr}}&g0.tab=1"

Anything else we need to know:
I think this is due to some html encoding of spaces:
we are seeing urls like:
https://<redacted>/graph?g0.expr=%28max&#43;by&#43;%28namespace%2C&#43;pod%2C&#43;instance%2C&#43;container%29&#43;%28increase%28kube_pod_container_status_restarts_total%7Bnamespace%21~%22openshift-gitops%7Copenshift-marketplace%7Copenshift-pipelines%22%2Cprometheus%3D%22platform%22%7D%5B1h%5D%29%29&#43;%3E%3D&#43;4%29&g0.tab=1

url decode:

When clicking on it, thanos query, opens it with:

https://<redacted>/graph?g0.expr=%20(max&g0.tab=1&g0.stacked=0&g0.range_input=1h&g0.max_source_resolution=0s&g0.deduplicate=1&g0.partial_response=0&g0.store_matches=%5B%5D&g0.engine=thanos&g0.analyze=0

[ahurtaud]

I think of an issue between difference of url encode and html encode :/
spaces becoming: + instead of %20 for example

[kartikaysaxena]

From what I get, we are using url.QueryEscape(expr) in tableLinkForExpression which may be the cause of it as it escapes certain special characters including + (for space) although we have to convert it into %20. Not doing so it in the first place makes it +

Edit: When the expression with + is passed in a new template, it makes the + + instead of %20.
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