Sourcemap will not link to correct line if media query is nested inside selector

When I compile Less with a sourcemap, and in the less file nest a media query inside a selector like so:

.post .title {
  @media(min-width: 700px) {
    display: flex;
  }
}

...and then use Chrome inspector to find the ruleset, I find it is always at the end of the file. However when I nest the entire ruleset in a media query like so:

@media(min-width: 700px) {
  .post .title {
    display: flex;
  }
}

...there is no problem and can find the ruleset on the correct line in the sourcemap, as opposed to at the end of the file.

If it helps I am using Node and compile Less v2.5.3 using grunt and the plugin grunt-contrib-less, I'm not sure if it is a Less issue and was wondering if this is something to be expected with Less sourcemaps.

Start by reproducing the nested media-query example with Less 2.5.3 and a sourcemap, then inspect the generated rule in Chrome and compare it with the outer-media-query case. Done means the nested rule maps to its correct Less source line instead of the end of the file.