新版本 jupyter 似乎导致 PDF 无法显示 / PDF display not working in newer versions of jupyter

[bryango]

看起来与 jupyter 的验证机制及 Chrome 的安全策略有关，参见 jupyter/notebook#3652.
Seemingly related to jupyter & Chrome's authentication process, see jupyter/notebook#3652.

暂时的解决方案 / Temporary fix：

1. 安装 PDF.js 插件 或使用 firefox / Use PDF.js extension for Chrome, or simply switch to firefox;
2. 在 exN.ipynb 中启用内置 PDF 阅读器模式，即修改初始化单元：

#pdfshowOption['mini'] = False
pdfshowOption['mini'] = True

[bryango]

确认问题由 jupyter 的安全更新 jupyter/notebook#3341 导致。
Due to the security measure introduced in jupyter/notebook#3341 it is nearly impossible to embed pdf in ipynb.

暴力的解决方案 / my fix：
更改 notebook 源码，强行干掉上述 PR!
Simply revert commits by aforementioned PR.

本人的 package 路径为：[...]/anaconda3/lib/python3.7/site-packages/notebook, 变更如下：

Subject: [PATCH] UN-patch #3341

---
 base/handlers.py  | 7 -------
 files/handlers.py | 7 -------
 2 files changed, 14 deletions(-)

diff --git a/base/handlers.py b/base/handlers.py
index e3fbddc..72677c9 100644
--- a/base/handlers.py
+++ b/base/handlers.py
@@ -640,13 +640,6 @@ class Template404(IPythonHandler):
 class AuthenticatedFileHandler(IPythonHandler, web.StaticFileHandler):
     """static files should only be accessible when logged in"""
 
-    @property
-    def content_security_policy(self):
-        # In case we're serving HTML/SVG, confine any Javascript to a unique
-        # origin so it can't interact with the notebook server.
-        return super(AuthenticatedFileHandler, self).content_security_policy + \
-                "; sandbox allow-scripts"
-
     @web.authenticated
     def get(self, path):
         if os.path.splitext(path)[1] == '.ipynb' or self.get_argument("download", False):
diff --git a/files/handlers.py b/files/handlers.py
index 7973fd6..b942149 100644
--- a/files/handlers.py
+++ b/files/handlers.py
@@ -26,13 +26,6 @@ class FilesHandler(IPythonHandler):
     a subclass of StaticFileHandler.
     """
 
-    @property
-    def content_security_policy(self):
-        # In case we're serving HTML/SVG, confine any Javascript to a unique
-        # origin so it can't interact with the notebook server.
-        return super(FilesHandler, self).content_security_policy + \
-               "; sandbox allow-scripts"
-
     @web.authenticated
     def head(self, path):
         self.get(path, include_body=False)
-- 
2.18.0

长远的解决方案得看 upstream 的 jupyter/notebook#3652, 本人无能为力。关闭 issue.