Mikrotik blocks part of the traffic when "Bridge" is enabled, what is the reason?

Question

Mikrotik

The situation is as follows: there is a remote office, Mikrotik is installed, the Internet is connected. A PPTP channel was raised to the head office in Mikrotik, an EoIP tunnel was laid on top.
At the remote office, ether2 (local network) and eoip tunnel are combined into a bridge.
The head office did not previously have a bridge to combine interfaces. Now needed. Created, added a local mesh port and an eoip tunnel to it. I make it active - some sites stop opening.
Where to dig to fix the problem - I do not understand.
UPD. If you exclude the EoIP interface from the bridge, then the sites open, but the connection to the second network segment is lost (which is logical)

Answer 1

If the problem is with TCP (HTTP), then look towards MSS

Answer 2

It looks like you have an IP address conflict between local networks.
at the time of the problem, try to trace to problematic resources and understand whether the route goes further than your router, and if it goes, then exactly where you need it (to the local gateway, and not through the tunnel to the remote one).
Need more information to understand the problem. What IP addresses are you using on each side? What are the routes on the routers?
Regarding the tunnel : Try to raise the sstp tunnel, it works with mtu=1500 on the tunnel and it can be perfectly included on both sides in the bridges of each side. And it's more secure than your choice.

Answer 3

I have the same problem with EoIP. Between offices PPTP is raised and over it EoIP. And the following picture is observed - the router starts to transfer the default router to the remote office. Those. I go online through a remote router. I can't figure out why this is happening.