Bug: Lag / Stack Overflow on Phoenix Search Result

**Describe the bug**
Stack overflow on long search result.

**To Reproduce**
Steps to reproduce the behavior:

1. Add Phoenix as a source.
2. Search for `testing-librar` (problem occurs when typing the second `r`)

Result:

Page lags for a while, then an error shows in the console. I can continue to interact with the page, but every action takes several seconds, until I delete the search term and the page becomes responsive again.

It freezes every time I search with `testing-librar` but does not reliably freeze when finding the same search result by searching for other terms.

**Expected behavior**
No lagging, text in search results is trimmed.
A clear and concise description of what you expected to happen.

**Screenshots**

**Desktop (please complete the following information):**
- OS: macOS Big Sur
- Browser: Firefox 95.0.1

**Additional context**
I recently started trying DevDocs for the first time. I added a few sources, and tried searching for a few terms, but it's otherwise a fresh state.

Phoenix をソースとして追加し、`testing-librar` を検索して問題を再現します。特に 2 つ目の `r` を入力する際に、ブラウザーコンソールでスタックオーバーフローが発生していないか確認します。検索が応答性を維持し、長い結果テキストが報告されたエラーなしでトリミングされれば完了です。

索引モデルが issue の本文から書いたものです。